WorldWideScience

Sample records for dual fuel compression

  1. Development of compressed natural gas/diesel dual-fuel turbocharged compressed ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Shenghua, L.; Ziyan, W.; Jiang, R. [Xi' an Jiaotong Univ. (China). Dept. of Automotive Engineering

    2003-09-01

    A natural gas and diesel dual-fuel turbocharged compression ignition (CI) engine is developed to reduce emissions of a heavy-duty diesel engine. The compressed natural gas (CNG) pressure regulator is specially designed to feed back the boost pressure to simplify the fuel metering system. The natural gas bypass improves the engine response to acceleration. The modes of diesel injection are set according to the engine operating conditions. The application of honeycomb mixers changes the flowrate shape of natural gas and reduces hydrocarbon (HC) emission under low-load and lowspeed conditions. The cylinder pressures of a CI engine fuelled with diesel and dual fuel are analysed. The introduction of natural gas makes the ignition delay change with engine load. Under the same operating conditions, the emissions of smoke and NO{sub x} from the dual-fuel engine are both reduced. The HC and CO emissions for the dual-fuel engine remain within the range of regulation. (Author)

  2. Combustion characteristics of compressed natural gas/diesel dual-fuel turbocharged compressed ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Shenghua, L.; Longbao, Z.; Ziyan, W.; Jiang, R. [Xi' an Jiaotong Univ. (China). Dept. of Automotive Engineering

    2003-09-01

    The combustion characteristics of a turbocharged natural gas and diesel dual-fuelled compression ignition (CI) engine are investigated. With the measured cylinder pressures of the engine operated on pure diesel and dual fuel, the ignition delay, effects of pilot diesel and engine load on combustion characteristics are analysed. Emissions of HC, CO, NO{sub x} and smoke are measured and studied too. The results show that the quantity of pilot diesel has important effects on the performance and emissions of a dual-fuel engine at low-load operating conditions. Ignition delay varies with the concentration of natural gas. Smoke is much lower for the developed dual-fuel engine under all the operating conditions. (Author)

  3. Studies on biogas-fuelled compression ignition engine under dual fuel mode.

    Science.gov (United States)

    Mahla, Sunil Kumar; Singla, Varun; Sandhu, Sarbjot Singh; Dhir, Amit

    2018-04-01

    Experimental investigation has been carried out to utilize biogas as an alternative source of energy in compression ignition (CI) engine under dual fuel operational mode. Biogas was inducted into the inlet manifold at different flow rates along with fresh air through inlet manifold and diesel was injected as a pilot fuel to initiate combustion under dual fuel mode. The engine performance and emission characteristics of dual fuel operational mode were analyzed at different biogas flow rates and compared with baseline conventional diesel fuel. Based upon the improved performance and lower emission characteristics under the dual fuel operation, the optimum flow rate of biogas was observed to be 2.2 kg/h. The lower brake thermal efficiency (BTE) and higher brake-specific energy consumption (BSEC) were noticed with biogas-diesel fuel under dual fuel mode when compared with neat diesel operation. Test results showed reduced NO x emissions and smoke opacity level in the exhaust tailpipe emissions. However, higher hydrocarbon (HC) and carbon monoxide (CO) emissions were noticed under dual fuel mode at entire engine loads when compared with baseline fossil petro-diesel. Hence, the use of low-cost gaseous fuel such as biogas would be an economically viable proposition to address the current and future problems of energy scarcity and associated environmental concerns.

  4. Compressed Biogas-Diesel Dual-Fuel Engine Optimization Study for Ultralow Emission

    Directory of Open Access Journals (Sweden)

    Hasan Koten

    2014-06-01

    Full Text Available The aim of this study is to find out the optimum operating conditions in a diesel engine fueled with compressed biogas (CBG and pilot diesel dual-fuel. One-dimensional (1D and three-dimensional (3D computational fluid dynamics (CFD code and multiobjective optimization code were employed to investigate the influence of CBG-diesel dual-fuel combustion performance and exhaust emissions on a diesel engine. In this paper, 1D engine code and multiobjective optimization code were coupled and evaluated about 15000 cases to define the proper boundary conditions. In addition, selected single diesel fuel (dodecane and dual-fuel (CBG-diesel combustion modes were modeled to compare the engine performances and exhaust emission characteristics by using CFD code under various operating conditions. In optimization study, start of pilot diesel fuel injection, CBG-diesel flow rate, and engine speed were optimized and selected cases were compared using CFD code. CBG and diesel fuels were defined as leading reactants using user defined code. The results showed that significantly lower NOx emissions were emitted under dual-fuel operation for all cases compared to single-fuel mode at all engine load conditions.

  5. Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot Diesel fuel and natural gas

    International Nuclear Information System (INIS)

    Papagiannakis, R.G.; Hountalas, D.T.

    2004-01-01

    Towards the effort of reducing pollutant emissions, especially soot and nitrogen oxides, from direct injection Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. These engines are known as dual fuel combustion engines, i.e. they use conventional Diesel fuel and a gaseous fuel as well. This technology is currently reintroduced, associated with efforts to overcome various difficulties of HCCI engines, using various fuels. The use of natural gas as an alternative fuel is a promising solution. The potential benefits of using natural gas in Diesel engines are both economical and environmental. The high autoignition temperature of natural gas is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under dual fuel conditions. The primary amount of fuel is the gaseous one, which is ignited by a pilot Diesel liquid injection. Comparative results are given for various engine speeds and loads for conventional Diesel and dual fuel operation, revealing the effect of dual fuel combustion on engine performance and exhaust emissions

  6. Dual-Fuel Combustion for Future Clean and Efficient Compression Ignition Engines

    Directory of Open Access Journals (Sweden)

    Jesús Benajes

    2016-12-01

    Full Text Available Stringent emissions limits introduced for internal combustion engines impose a major challenge for the research community. The technological solution adopted by the manufactures of diesel engines to meet the NOx and particle matter values imposed in the EURO VI regulation relies on using selective catalytic reduction and particulate filter systems, which increases the complexity and cost of the engine. Alternatively, several new combustion modes aimed at avoiding the formation of these two pollutants by promoting low temperature combustion reactions, are the focus of study nowadays. Among these new concepts, the dual-fuel combustion mode known as reactivity controlled compression ignition (RCCI seems more promising because it allows better control of the combustion process by means of modulating the fuel reactivity depending on the engine operating conditions. The present experimental work explores the potential of different strategies for reducing the energy losses with RCCI in a single-cylinder research engine, with the final goal of providing the guidelines to define an efficient dual-fuel combustion system. The results demonstrate that the engine settings combination, piston geometry modification, and fuel properties variation are good methods to increase the RCCI efficiency while maintaining ultra-low NOx and soot emissions for a wide range of operating conditions.

  7. Numerical investigation of the impact of gas composition on the combustion process in a dual-fuel compression-ignition engine

    NARCIS (Netherlands)

    Mikulski, M.; Wierzbicki, S.

    2016-01-01

    This study discusses the model of operation of a dual-fuel compression-ignition engine, powered by gaseous fuel with an initial dose of diesel fuel as the ignition inhibitor. The study used a zero-dimensional multiphase mathematical model of a dual-fuel engine to simulate the impact of enhancing

  8. Effect of compression ratio on performance, combustion and emission characteristics of a dual fuel diesel engine run on raw biogas

    International Nuclear Information System (INIS)

    Bora, Bhaskor J.; Saha, Ujjwal K.; Chatterjee, Soumya; Veer, Vijay

    2014-01-01

    Highlights: • Maximum brake thermal efficiency of 20.04% was obtained in dual fuel mode. • Compression ratio of 18 produced the maximum brake thermal efficiency. • Maximum replacement of diesel was found to be 79.46% at a compression ratio of 18. • CO gets reduced by 26.22% with the increase of compression ratio from 16 to18. • HC gets reduced by 41.97% with the increase of compression ratio from 16 to18. - Abstract: The energy consumption of the world is increasing at a staggering rate due to population explosion. The extensive use of energy has led to fossil fuel depletion and the rise in pollution. Renewable energy holds the key solution to these aforementioned problems. Biogas, one such renewable fuel, can be used in a diesel engine under dual fuel mode for the generation of power. This work attempts to unfold the effect of compression ratio on the performance, combustion and emission characteristics of a dual fuel diesel engine run on raw biogas. For this investigation, a 3.5 kW single cylinder, direct injection, water cooled, variable compression ratio diesel engine is converted into a biogas run dual fuel diesel engine by connecting a venturi gas mixer at the inlet manifold. Experiments have been conducted at various compression ratios (18, 17.5, 17 and 16) and under different loading conditions fixing the standard injection timing at 23° before top dead centre. At 100% load, the brake thermal efficiencies of the dual fuel mode are found to be 20.04%, 18.25%, 17.07% and 16.42% at compression ratios of 18, 17.5, 17 and 16, respectively, whereas at the same load, the diesel mode shows an efficiency of 27.76% at a compression ratio of 17.5. The maximum replacement of the precious fossil fuel is found to be 79.46%, 76.1%, 74% and 72% at compression ratios of 18, 17.5, 17 and 16, respectively at 100% load. For the dual fuel mode, on an average, there is a reduction in carbon monoxide as well as hydrocarbon emission by 26.22% and 41.97% when compression

  9. Numerical Investigation of Injection Timing Influence on Fuel Slip and Influence of Compression Ratio on Knock Occurrence in Conventional Dual Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mario Sremec

    2017-12-01

    Full Text Available Compressed natural gas can be used in diesel engine with great benefits, but because of its low reactivity it is usually used in a so called dual fuel combustion process. Optimal parameters for dual fuel engines are not yet investigated thoroughly which is the motivation for this work. In this work, a numerical study performed in a cycle simulation tool (AVL Boost v2013 on the influence of different injection timings on fuel slip into exhaust and influence of compression ratio on knock phenomena in port injected dual fuel engine was conducted. The introduction of natural gas into the intake port of a diesel engine usually results in some fuel slipping into the exhaust port due to valve overlap. By analysing the simulation results, the injection strategy that significantly decreases the natural gas slip is defined. The knock occurrence study showed that the highest allowed compression ratio that will result in knock free operation of the presented engine is 18 for ambient intake condition, while for charged intake conditions the compression ratio should be lowered to 16.

  10. Numerical and Experimental Investigation of Combustion and Knock in a Dual Fuel Gas/Diesel Compression Ignition Engine

    Directory of Open Access Journals (Sweden)

    A. Gharehghani

    2012-01-01

    Full Text Available Conventional compression ignition engines can easily be converted to a dual fuel mode of operation using natural gas as main fuel and diesel oil injection as pilot to initiate the combustion. At the same time, it is possible to increase the output power by increasing the diesel oil percentage. A detailed performance and combustion characteristic analysis of a heavy duty diesel engine has been studied in dual fuel mode of operation where natural gas is used as the main fuel and diesel oil as pilot. The influence of intake pressure and temperature on knock occurrence and the effects of initial swirl ratio on heat release rate, temperature-pressure and emission levels have been investigated in this study. It is shown that an increase in the initial swirl ratio lengthens the delay period for auto-ignition and extends the combustion period while it reduces NOx. There is an optimum value of the initial swirl ratio for a certain mixture intake temperature and pressure conditions that can achieve high thermal efficiency and low NOx emissions while decreases the tendency to knock. Simultaneous increase of intake pressure and initial swirl ratio could be the solution to power loss and knock in dual fuel engine.

  11. Validation of a zero-dimensional and 2-phase combustion model for dual-fuel compression ignition engine simulation

    Directory of Open Access Journals (Sweden)

    Mikulski Maciej

    2017-01-01

    Full Text Available Increasing demands for the reduction of exhaust emissions and the pursuit to re-duce the use of fossil fuels require the search for new fuelling technologies in combustion engines. One of the most promising technologies is the multi-fuel compression ignition engine concept, in which a small dose of liquid fuel injected directly into the cylinder acts as the ignition inhibitor of the gaseous fuel. Achieving the optimum combustion process in such an engine requires the application of advanced control algorithms which require mathematical modelling support. In response to the growing demand for new simulation tools, a 0-D model of a dual-fuel engine was proposed and validated. The validation was performed in a broad range of engine operating points, including various speeds and load condition, as well as different natural gas/diesel blend ratios. It was demonstrated that the average model calculation error within the entire cycle did not exceed 6.2%, and was comparable to the measurement results cycle to cycle variations. The maximum model calculation error in a single point of a cycle was 15% for one of the complex (multipoint injection cases. In other cases, it did not exceed 11%.

  12. Effect of engine load and biogas flow rate to the performance of a compression ignition engine run in dual-fuel (dieselbiogas) mode

    Science.gov (United States)

    Ambarita, H.

    2018-02-01

    The Government of Indonesia (GoI) has released a target on reduction Green Houses Gases emissions (GHG) by 26% from level business-as-usual by 2020, and the target can be up to 41% by international supports. In the energy sector, this target can be reached effectively by promoting fossil fuel replacement or blending with biofuel. One of the potential solutions is operating compression ignition (CI) engine in dual-fuel (diesel-biogas) mode. In this study effects of engine load and biogas flow rate on the performance and exhaust gas emissions of a compression ignition engine run in dual-fuel mode are investigated. In the present study, the used biogas is refined with methane content 70% of volume. The objectives are to explore the optimum operating condition of the CI engine run in dual-fuel mode. The experiments are performed on a four-strokes CI engine with rated output power of 4.41 kW. The engine is tested at constant speed 1500 rpm. The engine load varied from 600W to 1500W and biogas flow rate varied from 0 L/min to 6 L/min. The results show brake thermal efficiency of the engine run in dual-fuel mode is better than pure diesel mode if the biogas flow rates are 2 L/min and 4 L/min. It is recommended to operate the present engine in a dual-fuel mode with biogas flow rate of 4 L/min. The consumption of diesel fuel can be replaced up to 50%.

  13. Validation of a zero-dimensional and two-phase combustion model for dual-fuel compression ignition engine simulation

    NARCIS (Netherlands)

    Mikulski, M.; Wierzbicki, S.

    2017-01-01

    Increasing demands for the reduction of exhaust emissions and the pursuit to reduce the use of fossil fuels require the search for new fuelling technologies in combustion engines. One of the most promising technologies is the multi-fuel compression ignition engine concept, in which a small dose of

  14. An effort to enhance hydrogen energy share in a compression ignition engine under dual-fuel mode using low temperature combustion strategies

    International Nuclear Information System (INIS)

    Chintala, V.; Subramanian, K.A.

    2015-01-01

    Highlights: • H 2 energy share increased from 18% with DDM to 36% with WDM (water injection). • H 2 energy share improved marginally with retarded injection timing mode (RDM). • Energy efficiency increased with increasing amount of H 2 in dual-fuel engine. • NO x emission decreased with water injection and retarded pilot fuel injection. • HC, CO and smoke emissions increased slightly with low temperature combustion. - Abstract: A limited hydrogen (H 2 ) energy share due to knocking is the major hurdle for effective utilization of H 2 in compression ignition (CI) engines under dual-fuel operation. The present study aims at improvement of H 2 energy share in a 7.4 kW direct injection CI engine under dual-fuel mode with two low temperature combustion (LTC) strategies; (i) retarded pilot fuel injection timing and (ii) water injection. Experiments were carried out under conventional strategies of diesel dual-fuel mode (DDM) and B20 dual-fuel mode (BDM); and LTC strategies of retarded injection timing dual-fuel mode (RDM) and water injected dual-fuel mode (WDM). The results explored that the H 2 energy share increased significantly from 18% with conventional DDM to 24, and 36% with RDM, and WDM respectively. The energy efficiency increased with increasing H 2 energy share under dual-fuel operation; however, for a particular energy share of 18% H 2 , it decreased from 34.8% with DDM to 33.7% with BDM, 32.7% with WDM and 29.9% with RDM. At 18% H 2 energy share, oxides of nitrogen emission decreased by 37% with RDM and 32% with WDM as compared to conventional DDM due to reduction of in-cylinder temperature, while it increased slightly about 5% with BDM. It is emerged from the study that water injection technique is the viable option among all other strategies to enhance the H 2 energy share in the engine with a slight penalty of increase in smoke, hydrocarbon, and carbon monoxide emissions

  15. Notion Of Artificial Labs Slow Global Warming And Advancing Engine Studies Perspectives On A Computational Experiment On Dual-Fuel Compression-Ignition Engine Research

    Directory of Open Access Journals (Sweden)

    Tonye K. Jack

    2017-06-01

    Full Text Available To appreciate clean energy applications of the dual-fuel internal combustion engine D-FICE with pilot Diesel fuel to aid public policy formulation in terms of present and future benefits to the modern transportation stationary power and promotion of oil and gas green- drilling the brief to an engine research team was to investigate the feasible advantages of dual-fuel compression-ignition engines guided by the following concerns i Sustainable fuel and engine power delivery ii The requirements for fuel flexibility iii Low exhausts emissions and environmental pollution iv Achieving low specific fuel consumption and economy for maximum power v The comparative advantages over the conventional Diesel engines vi Thermo-economic modeling and analysis for the optimal blend as basis for a benefitcost evaluation Planned in two stages for reduced cost and fast turnaround of results - initial preliminary stage with basic simple models and advanced stage with more detailed complex modeling. The paper describes a simplified MATLAB based computational experiment predictive model for the thermodynamic combustion and engine performance analysis of dual-fuel compression-ignition engine studies operating on the theoretical limited-pressure cycle with several alternative fuel-blends. Environmental implications for extreme temperature moderation are considered by finite-time thermodynamic modeling for maximum power with predictions for pollutants formation and control by reaction rates kinetics analysis of systematic reduced plausible coupled chemistry models through the NCN reaction pathway for the gas-phase reactions classes of interest. Controllable variables for engine-out pollutants emissions reduction and in particular NOx elimination are identified. Verifications and Validations VampV through Performance Comparisons were made using a clinical approach in selection of StrokeBore ratios greater-than and equal-to one amp88051 low-to-high engine speeds and medium

  16. Effect of Hydrogen and Hydrogen Enriched Compressed Natural Gas Induction on the Performance of Rubber Seed Oil Methy Ester Fuelled Common Rail Direct Injection (CRDi Dual Fuel Engines

    Directory of Open Access Journals (Sweden)

    Mallikarjun Bhovi

    2017-06-01

    Full Text Available Renewable fuels are in biodegradable nature and they tender good energy security and foreign exchange savings. In addition they address environmental concerns and socio-economic issues. The present work presents the experimental investigations carried out on the utilization of such renewable fuel combinations for diesel engine applications. For this a single-cylinder four-stroke water cooled direct injection (DI compression ignition (CI engine provided with CMFIS (Conventional Mechanical Fuel Injection System was rightfully converted to operate with CRDi injection systems enabling high pressure injection of Rubber seed oil methyl ester (RuOME in the dual fuel mode with induction of varied gas flow rates of hydrogen and hydrogen enriched CNG (HCNG gas combinations. Experimental investigations showed a considerable improvement in dual fuel engine performance with acceptable brake thermal efficiency and reduced emissions of smoke, hydrocarbon (HC, carbon monoxide (CO and slightly increased nitric oxide (NOx emission levels for increased hydrogen and HCNG flow rates. Further CRDi facilitated dual fuel engine showed improved engine performance compared to CMFIS as the former enabled high pressure (900 bar injection of the RuOME and closer to TDC (Top Dead Centre as well. Combustion parameters such as ignition delay, combustion duration, pressure-crank angle and heat release rates were analyzed and compared with baseline data generated. Combustion analysis showed that the rapid rate of burning of hydrogen and HCNG along with air mixtures increased due to presence of hydrogen in total and in partial combination with CNG which further resulted into higher cylinder pressures and energy release rates. However, sustained research that can provide feasible engine technology operating on such fuels in dual fuel operation can pave the way for continued fossil fuel usage.

  17. Dual Tank Fuel System

    Science.gov (United States)

    Wagner, Richard William; Burkhard, James Frank; Dauer, Kenneth John

    1999-11-16

    A dual tank fuel system has primary and secondary fuel tanks, with the primary tank including a filler pipe to receive fuel and a discharge line to deliver fuel to an engine, and with a balance pipe interconnecting the primary tank and the secondary tank. The balance pipe opens close to the bottom of each tank to direct fuel from the primary tank to the secondary tank as the primary tank is filled, and to direct fuel from the secondary tank to the primary tank as fuel is discharged from the primary tank through the discharge line. A vent line has branches connected to each tank to direct fuel vapor from the tanks as the tanks are filled, and to admit air to the tanks as fuel is delivered to the engine.

  18. An assessment of the dual-mode reactivity controlled compression ignition/conventional diesel combustion capabilities in a EURO VI medium-duty diesel engine fueled with an intermediate ethanol-gasoline blend and biodiesel

    International Nuclear Information System (INIS)

    Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Balloul, Iyad; Pradel, Gérard

    2016-01-01

    Highlights: • Reactivity controlled compression ignition regime utilized from 25% to 35% load. • Dual-mode reduces the regeneration periods of the diesel particulate filter. • The use of near-term available biofuels allows good performance and emissions. • Dual-mode leads to 2% greater efficiency than diesel combustion at high engine speeds. - Abstract: This work investigates the capabilities of the dual-mode reactivity controlled compression ignition/conventional diesel combustion engine operation to cover the full operating range of a EURO VI medium-duty diesel engine with compression ratio of 17.5:1. This concept is based on covering all the engine map switching between the reactivity controlled compression ignition and the conventional diesel combustion operating modes. Specifically, the benefits of reactivity controlled compression ignition combustion are exploited whenever possible according to certain restrictions, while the conventional diesel combustion operation is used to cover the zones of the engine map in which the reactivity controlled compression ignition operation is limited. The experiments were conducted using a single-cylinder research diesel engine derived from the multi-cylinder production engine. In addition, considering the mandatory presence of biofuels in the future context of road transport and the ability of ethanol to be blended with gasoline, the low reactivity fuel used in the study is a blend of 20% ethanol by volume with 80% of 95 octane number gasoline. Moreover, a diesel containing 7% of biodiesel has been used as high reactivity fuel. Firstly, a reactivity controlled compression ignition mapping is performed to check the operational limits of the concept in this engine platform. Later, based on the results, the potential of the dual-mode concept is discussed. Results suggest that, under the constraints imposed, reactivity controlled compression ignition combustion can be utilized between 25% and 35% load. In this region

  19. Compressed gas fuel storage system

    Science.gov (United States)

    Wozniak, John J.; Tiller, Dale B.; Wienhold, Paul D.; Hildebrand, Richard J.

    2001-01-01

    A compressed gas vehicle fuel storage system comprised of a plurality of compressed gas pressure cells supported by shock-absorbing foam positioned within a shape-conforming container. The container is dimensioned relative to the compressed gas pressure cells whereby a radial air gap surrounds each compressed gas pressure cell. The radial air gap allows pressure-induced expansion of the pressure cells without resulting in the application of pressure to adjacent pressure cells or physical pressure to the container. The pressure cells are interconnected by a gas control assembly including a thermally activated pressure relief device, a manual safety shut-off valve, and means for connecting the fuel storage system to a vehicle power source and a refueling adapter. The gas control assembly is enclosed by a protective cover attached to the container. The system is attached to the vehicle with straps to enable the chassis to deform as intended in a high-speed collision.

  20. Dual fuel injection piggyback controller system

    Science.gov (United States)

    Muji, Siti Zarina Mohd.; Hassanal, Muhammad Amirul Hafeez; Lee, Chua King; Fawzi, Mas; Zulkifli, Fathul Hakim

    2017-09-01

    Dual-fuel injection is an effort to reduce the dependency on diesel and gasoline fuel. Generally, there are two approaches to implement the dual-fuel injection in car system. The first approach is changing the whole injector of the car engine, the consequence is excessive high cost. Alternatively, it also can be achieved by manipulating the system's control signal especially the Electronic Control Unit (ECU) signal. Hence, the study focuses to develop a dual injection timing controller system that likely adopted to control injection time and quantity of compressed natural gas (CNG) and diesel fuel. In this system, Raspberry Pi 3 reacts as main controller unit to receive ECU signal, analyze it and then manipulate its duty cycle to be fed into the Electronic Driver Unit (EDU). The manipulation has changed the duty cycle to two pulses instead of single pulse. A particular pulse mainly used to control injection of diesel fuel and another pulse controls injection of Compressed Natural Gas (CNG). The test indicated promising results that the system can be implemented in the car as piggyback system. This article, which was originally published online on 14 September 2017, contained an error in the acknowledgment section. The corrected acknowledgment appears in the Corrigendum attached to the pdf.

  1. Towards model-based control of RCCI-CDF mode-switching in dual fuel engines

    NARCIS (Netherlands)

    Indrajuana, Armando; Bekdemir, C.; Feru, E.; Willems, F.P.T.

    2018-01-01

    The operation of a dual fuel combustion engine using combustion mode-switching offers the benefit of higher thermal efficiency compared to single-mode operation. For various fuel combinations, the engine research community has shown that running dual fuel engines in Reactivity Controlled Compression

  2. Sensitivity of dual fuel engine combustion and knocking limits to gaseous fuel composition

    Energy Technology Data Exchange (ETDEWEB)

    Selim, M.Y.E. [United Arab Emirates University, Al-Ain (United Arab Emirates). Dept. of Mechanical Engineering

    2004-02-01

    Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating variables are stored in a PC for off line analysis. The effects of engine speeds, loads, pilot injection angle, pilot fuel quantity and compression ratio on combustion noise, knocking torque, thermal efficiency and maximum pressure are examined for the dual engine running on the three gaseous fuels separately. The combustion noise, knocking and ignition limits are found to relate to the type of gaseous fuels and to the engine design and operating parameters. (author)

  3. Sensitivity of dual fuel engine combustion and knocking limits to gaseous fuel composition

    International Nuclear Information System (INIS)

    Selim, Mohamed Y.E.

    2004-01-01

    Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating variables are stored in a PC for off line analysis. The effects of engine speeds, loads, pilot injection angle, pilot fuel quantity and compression ratio on combustion noise, knocking torque, thermal efficiency and maximum pressure are examined for the dual engine running on the three gaseous fuels separately. The combustion noise, knocking and ignition limits are found to relate to the type of gaseous fuels and to the engine design and operating parameters

  4. Experimental investigation of performance, exhaust emission and combustion parameters of stationary compression ignition engine using ethanol fumigation in dual fuel mode

    International Nuclear Information System (INIS)

    Jamuwa, D.K.; Sharma, D.; Soni, S.L.

    2016-01-01

    Highlights: • Potential of renewable fuels as diesel replacement is being emphasized. • Effect of ethanol fumigation on the performance of diesel engine is investigated. • NOx, CO_2 and smoke decreases with simultaneous increase in HC and CO. • Increase in ignition delay with decrease in combustion duration for ethanol substitution observed. - Abstract: Dwindling reserves and steeply increasing prices of the fossil-fuels, concern over climatic change due to release of anthropogenic greenhouse gases and the strict environmental regulations have motivated the researchers for the search for renewable alternative fuel that has clean burning characteristics and may be produced indigenously. Alcohols, being oxygenated fuel improve the combustion and reduce greenhouse gas emissions, thus enhancing agrarian economies and encouraging national economy as a whole. The objective of this paper is to investigate the thermal performance, exhaust emissions and combustion behaviour of small capacity compression ignition engine using fumigated ethanol. Fumigated ethanol at different flow rates is supplied to the cylinder during suction with the help of a simplified low cost ethanol fuelling system. With ethanol fumigation, brake thermal efficiency decreased upto 11.2% at low loads due to deteriorated combustion, whereas improved combustion increased efficiency up to 6% at higher loads, as compared to pure diesel. Maximum reduction of 22%, 41% and 27% respectively in nitrogen oxide, smoke and carbon-di-oxide emissions with simultaneous increase in hydrocarbon and carbon-mono-oxide emissions upto maximum of 144% and 139% respectively for different rates of ethanol fumigation have been observed, when compared to pure diesel operation. This is due to the changes in physico-chemical properties of air fuel mixture, viz combustion temperature, oxygen concentration, latent heat of vaporisation, fuel distribution, cetane number and ignition delay, that occurred with addition of

  5. Hydrogen energy share improvement along with NOx (oxides of nitrogen) emission reduction in a hydrogen dual-fuel compression ignition engine using water injection

    International Nuclear Information System (INIS)

    Chintala, V.; Subramanian, K.A.

    2014-01-01

    Highlights: • H 2 energy share increased from 20% without water to 39% with SWC 270 g/kWh. • Specific water consumption (SWC) 200 g/kWh was selected as the optimum quantity. • NO x decreased about 24% with the optimum water quantity at 20% H 2 energy share. • At 20% H 2 share, energy efficiency decreased about 5.5% with the optimum water. • HC, CO and smoke emissions increased 38%, 100% and 69% with optimum water at 20% H 2 share. - Abstract: The study aims at enhancement of Hydrogen (H 2 ) energy share and reduction of Oxides of Nitrogen (NO x ) emission in a 7.4 kW-CI engine at 1500 rpm using water injection. The test engine was modified to run under dual-fuel operation with diesel–biodiesel blend (B20) and H 2 fuels for different Specific Water Consumption (SWC) of 130, 200, and 270 g/kWh. Under conventional H 2 dual-fuel mode, energy efficiency and NO x emission increased significantly while Hydrocarbon (HC), Carbon Monoxide (CO) and smoke emissions decreased. The maximum H 2 energy share increased from 20% without water to 32%, 36%, and 39% with SWC of 130, 200, and 270 g/kWh respectively. However, SWC of 200 g/kWh was selected as an optimum water quantity for knock free operation, better performance and lower emissions. At the optimum SWC with 20% H 2 energy share, the NO x emission and energy efficiency decreased about 24% and 5.7%, while HC and smoke emissions increased about 38% and 69%. At 20% H 2 energy share, the CO emission increased from 0.0 g/kWh without water to 1.2 g/kWh with the optimum SWC. However, reduction of these HC and CO emissions using oxidation catalysts needs to be studied further. A new methodology for determining heat release rate with consideration of crevice gas was proposed in the study

  6. Dual compression is not an uncommon type of iliac vein compression syndrome.

    Science.gov (United States)

    Shi, Wan-Yin; Gu, Jian-Ping; Liu, Chang-Jian; Lou, Wen-Sheng; He, Xu

    2017-09-01

    Typical iliac vein compression syndrome (IVCS) is characterized by compression of left common iliac vein (LCIV) by the overlying right common iliac artery (RCIA). We described an underestimated type of IVCS with dual compression by right and left common iliac arteries (LCIA) simultaneously. Thirty-one patients with IVCS were retrospectively included. All patients received trans-catheter venography and computed tomography (CT) examinations for diagnosing and evaluating IVCS. Late venography and reconstructed CT were used for evaluating the anatomical relationship among LCIV, RCIA and LCIA. Imaging manifestations as well as demographic data were collected and evaluated by two experienced radiologists. Sole and dual compression were found in 32.3% (n = 10) and 67.7% (n = 21) of 31 patients respectively. No statistical differences existed between them in terms of age, gender, LCIV diameter at the maximum compression point, pressure gradient across stenosis, and the percentage of compression level. On CT and venography, sole compression was commonly presented with a longitudinal compression at the orifice of LCIV while dual compression was usually presented as two types: one had a lengthy stenosis along the upper side of LCIV and the other was manifested by a longitudinal compression near to the orifice of external iliac vein. The presence of dual compression seemed significantly correlated with the tortuous LCIA (p = 0.006). Left common iliac vein can be presented by dual compression. This type of compression has typical manifestations on late venography and CT.

  7. Fuel column retainer using radially compressed spring

    International Nuclear Information System (INIS)

    Johansson, E.B.

    1989-01-01

    This patent describes a fuel rod construction including a fuel rod having an inside cylindrical diameter, cylindrical fuel pellets placed within the rod. The cylindrical fuel pellets having a diameter less than the inside cylindrical diameter and being stacked end to end for a distance less than the length of the fuel rod inside the fuel rod; Zircaloy end plugs for sealing the rod at either end; a compression spring adjacent one end of the rods for biasing the pellets to and towards the other end of the rod. An improvement in the Zircaloy spring is described

  8. Comportamento de um motor de ignição por compressão trabalhando com óleo Diesel e gás natural A dual fuel compression ignition engine performance, running with Diesel fuel and natural gas

    Directory of Open Access Journals (Sweden)

    José F. Schlosser

    2004-12-01

    Full Text Available A previsível escassez de petróleo aliada a uma consciência ecológica está levando pesquisadores a procurar novas fontes de energia e processos de combustão mais eficientes e menos poluentes. Entre os combustíveis menos poluentes está o gás natural, cujo consumo aumenta ano a ano. Os motores de combustão interna são transformadores de energia que têm baixa eficiência de conversão. Este trabalho avaliou um motor Diesel, bicombustível, movido a Diesel e gás natural. Nesse motor, a energia provém, basicamente, da combustão do gás natural. O Diesel tem a função de produzir o início da combustão do gás, que é o combustível principal. Assim, haverá uma substituição parcial de óleo Diesel por gás natural, aumentando o rendimento da combustão. Inicialmente, foi feito um ensaio-testemunha, somente com óleo Diesel e após foram feitos ensaios, com três repetições, para variadas proporções de óleo Diesel, gás natural e ângulos de avanço da injeção. O melhor desempenho foi obtido para 22% de óleo Diesel em relação ao máximo débito da bomba injetora e 13 L min-1 de gás natural com ângulo de avanço de injeção original (21º. Nesse caso, a potência média aumentou 14%, e o consumo específico (medido em valores monetários diminuiu 46% em relação ao ensaio-testemunha.The foresight of a petroleum shortage and an ecological conscience is moving scientists to look for new sources of energy and to develop more efficient combustion processes and reduced emissions. Natural gas is a reduced emission fuel, whose consumption increases every year. The present work evaluates a dual fuel compression ignition engine. The major portion of the fuel burned is natural gas. The Diesel fuel acts as combustion starter, which ignites under the compression heat. Diesel fuel is used only as an ignition source. The partial substitution of Diesel fuel by natural gas increases the combustion efficiency and achieves significant

  9. Advanced compressed hydrogen fuel storage systems

    International Nuclear Information System (INIS)

    Jeary, B.

    2000-01-01

    Dynetek was established in 1991 by a group of private investors, and since that time efforts have been focused on designing, improving, manufacturing and marketing advanced compressed fuel storage systems. The primary market for Dynetek fuel systems has been Natural Gas, however as the automotive industry investigates the possibility of using hydrogen as the fuel source solution in Alternative Energy Vehicles, there is a growing demand for hydrogen storage on -board. Dynetek is striving to meet the needs of the industry, by working towards developing a fuel storage system that will be efficient, economical, lightweight and eventually capable of storing enough hydrogen to match the driving range of the current gasoline fueled vehicles

  10. Exhaust emissions from an indirect injection dual-fuel engine

    International Nuclear Information System (INIS)

    Abd Alla, G.H.; Badr, O.A.; Soliman, H.A.; Abd Rabbo, M.F.

    2000-01-01

    Diesel engines operating on gaseous fuels are commonly known as dual-fuel engines. In the present work, a single-cylinder, compression ignition, indirect injection research (Ricardo E6) engine has been installed at United Arab Emirates University for investigation of the exhaust emissions when the engine is operating as a dual-fuel engine. The influence of changes in major operating and design parameters, such as the concentration of gaseous fuel in the cylinder charge, pilot fuel quantity, injection timing and intake temperature, on the production of exhaust emissions was investigated. Diesel fuel was used as the pilot fuel, while methane or propane was used as the main fuel which was inducted in the intake manifold and mixed with the intake air. The experimental investigations showed that the poor emissions at light loads can be improved significantly by increasing the concentration of gaseous fuel (total equivalence ratio), employing a large pilot fuel quantity, advancing the injection timing of the pilot fuel and increasing the intake temperature. It is demonstrated that, in general, any measure that tends to increase the size of the combustion regions within the overly lean cylinder charge will reduce markedly the concentrations of unburned hydrocarbons and carbon monoxide in the exhaust gases. (Author)

  11. Exhaust emissions from an indirect injection dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Abd Alla, G.H.; Badr, O.A.; Soliman, H.A.; Abd Rabbo, M.F. [Zagazig Univ., Dept. of Mechanical Engineering, Cairo (Egypt)

    2000-04-01

    Diesel engines operating on gaseous fuels are commonly known as dual-fuel engines. In the present work, a single-cylinder, compression ignition, indirect injection research (Ricardo E6) engine has been installed at United Arab Emirates University for investigation of the exhaust emissions when the engine is operating as a dual-fuel engine. The influence of changes in major operating and design parameters, such as the concentration of gaseous fuel in the cylinder charge, pilot fuel quantity, injection timing and intake temperature, on the production of exhaust emissions was investigated. Diesel fuel was used as the pilot fuel, while methane or propane was used as the main fuel which was inducted in the intake manifold and mixed with the intake air. The experimental investigations showed that the poor emissions at light loads can be improved significantly by increasing the concentration of gaseous fuel (total equivalence ratio), employing a large pilot fuel quantity, advancing the injection timing of the pilot fuel and increasing the intake temperature. It is demonstrated that, in general, any measure that tends to increase the size of the combustion regions within the overly lean cylinder charge will reduce markedly the concentrations of unburned hydrocarbons and carbon monoxide in the exhaust gases. (Author)

  12. Superplastic boronizing of duplex stainless steel under dual compression method

    International Nuclear Information System (INIS)

    Jauhari, I.; Yusof, H.A.M.; Saidan, R.

    2011-01-01

    Highlights: → Superplastic boronizing. → Dual compression method has been developed. → Hard boride layer. → Bulk deformation was significantly thicker the boronized layer. → New data on boronizing could be expanded the application of DSS in industries. - Abstract: In this work, SPB of duplex stainless steel (DSS) under compression method is studied with the objective to produce ultra hard and thick boronized layer using minimal amount of boron powder and at a much faster boronizing time as compared to the conventional process. SPB is conducted under dual compression methods. In the first method DSS is boronized using a minimal amount of boron powder under a fix pre-strained compression condition throughout the process. The compression strain is controlled in such a way that plastic deformation is restricted at the surface asperities of the substrate in contact with the boron powder. In the second method, the boronized specimen taken from the first mode is compressed superplastically up to a certain compressive strain under a certain strain rate condition. The process in the second method is conducted without the present of boron powder. As compared with the conventional boronizing process, through this SPB under dual compression methods, a much harder and thicker boronized layer thickness is able to be produced using a minimal amount of boron powder.

  13. Superplastic boronizing of duplex stainless steel under dual compression method

    Energy Technology Data Exchange (ETDEWEB)

    Jauhari, I., E-mail: iswadi@um.edu.my [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Yusof, H.A.M.; Saidan, R. [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2011-10-25

    Highlights: {yields} Superplastic boronizing. {yields} Dual compression method has been developed. {yields} Hard boride layer. {yields} Bulk deformation was significantly thicker the boronized layer. {yields} New data on boronizing could be expanded the application of DSS in industries. - Abstract: In this work, SPB of duplex stainless steel (DSS) under compression method is studied with the objective to produce ultra hard and thick boronized layer using minimal amount of boron powder and at a much faster boronizing time as compared to the conventional process. SPB is conducted under dual compression methods. In the first method DSS is boronized using a minimal amount of boron powder under a fix pre-strained compression condition throughout the process. The compression strain is controlled in such a way that plastic deformation is restricted at the surface asperities of the substrate in contact with the boron powder. In the second method, the boronized specimen taken from the first mode is compressed superplastically up to a certain compressive strain under a certain strain rate condition. The process in the second method is conducted without the present of boron powder. As compared with the conventional boronizing process, through this SPB under dual compression methods, a much harder and thicker boronized layer thickness is able to be produced using a minimal amount of boron powder.

  14. Effect of pilot fuel quantity on the performance of a dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Abd Alla, G.H.; Soliman, H.A.; Badr, O.A.; Abd Rabbo, M.F. [Zagazig University, Cairo (Egypt). Shoubra Faculty of Engineering

    2000-04-01

    It is well known that the operation of dual fuel engines at lower loads suffers from lower thermal efficiency and higher unburned percentages of fuel. To rectify this problem, tests have been conducted on a special single cylinder compression ignition research engine (Ricardo E6) to investigate the effect of pilot fuel quantity on the performance of an indirect injection diesel engine fuelled with gaseous fuel. Diesel fuel was used as the pilot fuel and methane or propane was used as the main fuel which was inducted into the intake manifold to mix with the intake air. Through experimental investigations, it is shown that, the low efficiency and excess emissions at light loads can be improved significantly by increasing the amount of pilot fuel, while increasing the amount of pilot fuel at high loads led to early knocking. (author)

  15. EFFECT OF COMPRESSION RATIO ON ENERGY AND EMISSION OF VCR DIESEL ENGINE FUELLED WITH DUAL BLENDS OF BIODIESEL

    Directory of Open Access Journals (Sweden)

    R. D. EKNATH

    2014-10-01

    Full Text Available In recent 10 years biodiesel fuel was studied extensively as an alternative fuel. Most of researchers reported performance and emission of biodiesel and their blends with constant compression ratio. Also all the research was conducted with use of single biodiesel and its blend. Few reports are observed with the use of variable compression ratio and blends of more than one biodiesel. Main aim of the present study is to analyse the effect of compression ratio on the performance and emission of dual blends of biodiesel. In the present study Blends of Jatropha and Karanja with Diesel fuel was tested on single cylinder VCR DI diesel engine for compression ratio 16 and 18. High density of biodiesel fuel causes longer delay period for Jatropha fuel was observed compare with Karanja fuel. However blending of two biodiesel K20J40D results in to low mean gas temperature which is the main reason for low NOx emission.

  16. Effect of exhaust gas recirculation on some combustion characteristics of dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Selim, Mohamed Y.E. [United Arab Emirates Univ., Dept. of Mechanical Engineering, Al-Ain (United Arab Emirates)

    2003-03-01

    Combustion pressure rise rate and thermal efficiency data are measured and presented for a dual fuel engine running on a dual fuel of Diesel and compressed natural gas and utilizing exhaust gas recirculation (EGR). The maximum pressure rise rate during combustion is presented as a measure of combustion noise. The experimental investigation on the dual fuel engine revealed the noise generated from combustion and the thermal efficiency at different EGR ratios. A Ricardo E6 Diesel version engine is converted to run on a dual fuel of Diesel and compressed natural gas and having an exhaust gas recycling system is used throughout the work. The engine is fully computerized, and the cylinder pressure data and crank angle data are stored in a PC for offline analysis. The effects of EGR ratio, engine speeds, loads, temperature of recycled exhaust gases, intake charge pressure and engine compression ratio on combustion noise and thermal efficiency are examined for the dual fuel engine. The combustion noise and thermal efficiency of the dual fuel engine are found to be affected when EGR is used in the dual fuel engine. (Author)

  17. Dual pathology proximal median nerve compression of the forearm.

    LENUS (Irish Health Repository)

    Murphy, Siun M

    2013-12-01

    We report an unusual case of synchronous pathology in the forearm- the coexistence of a large lipoma of the median nerve together with an osteochondroma of the proximal ulna, giving rise to a dual proximal median nerve compression. Proximal median nerve compression neuropathies in the forearm are uncommon compared to the prevalence of distal compression neuropathies (eg Carpal Tunnel Syndrome). Both neural fibrolipomas (Refs. 1,2) and osteochondromas of the proximal ulna (Ref. 3) in isolation are rare but well documented. Unlike that of a distal compression, a proximal compression of the median nerve will often have a definite cause. Neural fibrolipoma, also called fibrolipomatous hamartoma are rare, slow-growing, benign tumours of peripheral nerves, most often occurring in the median nerve of younger patients. To our knowledge, this is the first report of such dual pathology in the same forearm, giving rise to a severe proximal compression of the median nerve. In this case, the nerve was being pushed anteriorly by the osteochondroma, and was being compressed from within by the intraneural lipoma. This unusual case highlights the advantage of preoperative imaging as part of the workup of proximal median nerve compression.

  18. Dual pathology proximal median nerve compression of the forearm.

    Science.gov (United States)

    Murphy, Siun M; Browne, Katherine; Tuite, David J; O'Shaughnessy, Michael

    2013-12-01

    We report an unusual case of synchronous pathology in the forearm- the coexistence of a large lipoma of the median nerve together with an osteochondroma of the proximal ulna, giving rise to a dual proximal median nerve compression. Proximal median nerve compression neuropathies in the forearm are uncommon compared to the prevalence of distal compression neuropathies (eg Carpal Tunnel Syndrome). Both neural fibrolipomas (Refs. 1,2) and osteochondromas of the proximal ulna (Ref. 3) in isolation are rare but well documented. Unlike that of a distal compression, a proximal compression of the median nerve will often have a definite cause. Neural fibrolipoma, also called fibrolipomatous hamartoma are rare, slow-growing, benign tumours of peripheral nerves, most often occurring in the median nerve of younger patients. To our knowledge, this is the first report of such dual pathology in the same forearm, giving rise to a severe proximal compression of the median nerve. In this case, the nerve was being pushed anteriorly by the osteochondroma, and was being compressed from within by the intraneural lipoma. This unusual case highlights the advantage of preoperative imaging as part of the workup of proximal median nerve compression. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  19. Demonstration and evaluation of dual-fuel technology; Demonstration och utvaerdering av dual-fuel-tekniken

    Energy Technology Data Exchange (ETDEWEB)

    Staalhammar, Per; Erlandsson, Lennart; Willner, Kristina (AVL MTC Motortestcenter AB (Sweden)); Johannesson, Staffan (Ecoplan AB (Sweden))

    2011-06-15

    There is an increased interest for Dual Fuel (methane-Diesel) applications in Sweden since this technology is seen as one of the more interesting options for a fast and cost effective introduction of biomethane as fuel for HD engines. The Dual Fuel technology has been used for many years, mainly for stationary purpose (generators, pumps and ships) while the Spark Ignited (SI) 'Otto' technology has been used for trucks and busses. One obstacle for introducing Dual Fuel technology for busses and trucks is the EU legislation that don't allow for HD on road certification of Dual Fuel applications. Challenges with the Dual Fuel technology is to develop cost effective applications that is capable of reaching low emissions (especially CH{sub 4} and NO{sub x}) in combination with high Diesel replacement in the test cycles used for on road applications. AVL MTC Motortestcenter AB (hereinafter called AVL) has on commission by SGC (Swedish Gas technical Centre) carried out this project with the objectives to analyze the Dual Fuel (Diesel-methane) technology with focus on emissions, fuel consumption and technical challenges. One important part of this project was to carry out emission tests on selected Dual Fuel applications in Sweden and to compile experiences from existing Dual Fuel technology. This report also summarizes other commonly used technologies for methane engines and compares the Dual Fuel with conventional Diesel and Otto technologies. The major challenges with Dual Fuel applications for on road vehicles will be to develop robust and cost effective solutions that meet the emission legislations (with aged catalysts) and to increase the Diesel replacement to achieve reasonable reduction of green house gases (GHG). This is especially important when biomethane is available as fuel but not Bio-Diesel. It will probably be possible to reach EURO V emission limits with advanced Dual Fuel systems but none of the tested systems reached EURO V emission levels

  20. Modelling for Fuel Optimal Control of a Variable Compression Engine

    OpenAIRE

    Nilsson, Ylva

    2007-01-01

    Variable compression engines are a mean to meet the demand on lower fuel consumption. A high compression ratio results in high engine efficiency, but also increases the knock tendency. On conventional engines with fixed compression ratio, knock is avoided by retarding the ignition angle. The variable compression engine offers an extra dimension in knock control, since both ignition angle and compression ratio can be adjusted. The central question is thus for what combination of compression ra...

  1. Dual fuel gradients in uranium silicide plates

    Energy Technology Data Exchange (ETDEWEB)

    Pace, B.W. [Babock and Wilcox, Lynchburg, VA (United States)

    1997-08-01

    Babcock & Wilcox has been able to achieve dual gradient plates with good repeatability in small lots of U{sub 3}Si{sub 2} plates. Improvements in homogeneity and other processing parameters and techniques have allowed the development of contoured fuel within the cladding. The most difficult obstacles to overcome have been the ability to evaluate the bidirectional fuel loadings in comparison to the perfect loading model and the different methods of instilling the gradients in the early compact stage. The overriding conclusion is that to control the contour of the fuel, a known relationship between the compact, the frames and final core gradient must exist. Therefore, further development in the creation and control of dual gradients in fuel plates will involve arriving at a plausible gradient requirement and building the correct model between the compact configuration and the final contoured loading requirements.

  2. Understanding the role of low reactivity fuel stratification in a dual fuel RCCI engine – A simulation study

    NARCIS (Netherlands)

    Mikulski, M.; Bekdemir, C.

    2017-01-01

    Natural gas - diesel, Reactivity Controlled Compression Ignition (RCCI) is currently one of the most promising combustion strategies for the next generation heavy-duty engines. A major issue to be addressed for this dual fuel concept to become practically applicable is its low combustion efficiency

  3. Improving the performance of dual fuel engines running on natural gas/LPG by using pilot fuel derived from jojoba seeds

    Energy Technology Data Exchange (ETDEWEB)

    Selim, Mohamed Y.E. [Mechanical Engineering Department, College of Engineering, UAE University, Jimmi, Al-Ain, P.O. Box 17555, Abu Dhabi (United Arab Emirates); Radwan, M.S.; Saleh, H.E. [Mechanical Power Engineering Department, Faculty of Engineering at Mattaria, Helwan University, Cairo (Egypt)

    2008-06-15

    The use of jojoba methyl ester as a pilot fuel was investigated for almost the first time as a way to improve the performance of dual fuel engine running on natural gas or liquefied petroleum gas (LPG) at part load. The dual fuel engine used was Ricardo E6 variable compression diesel engine and it used either compressed natural gas (CNG) or LPG as the main fuel and jojoba methyl ester as a pilot fuel. Diesel fuel was used as a reference fuel for the dual fuel engine results. During the experimental tests, the following have been measured: engine efficiency in terms of specific fuel consumption, brake power output, combustion noise in terms of maximum pressure rise rate and maximum pressure, exhaust emissions in terms of carbon monoxide and hydrocarbons, knocking limits in terms of maximum torque at onset of knocking, and cyclic variability data of 100 engine cycles in terms of maximum pressure and its pressure rise rate average and standard deviation. The tests examined the following engine parameters: gaseous fuel type, engine speed and load, pilot fuel injection timing, pilot fuel mass and compression ratio. Results showed that using the jojoba fuel with its improved properties has improved the dual fuel engine performance, reduced the combustion noise, extended knocking limits and reduced the cyclic variability of the combustion. (author)

  4. Use of a non-edible vegetable oils as an alternative fuel in compression ignition engines

    International Nuclear Information System (INIS)

    Jayaraj, S.; Ramadhas, A.S.; Muraleedharan, C.

    2006-01-01

    Shortage of petroleum fuels is assumed predominance globally and hence efforts are being made in every country to look for alternative fuels, especially for running internal compression ignition engines. However, the limited availability of edible vegetable oils in excess amounts is a limiting factors, which limits their large usage as an alternative fuel. A remedy for this is the use of non-edible oils obtained mainly from seeds, which are otherwise dumped as waste material. An effort is made here to use rubber seed oil as fuel in compression ignition engine at various proportions, mixed with diesel oil. The performance and emission characteristics of the engine are measured under dual fuel operation. The compression ignition engine could be run satisfactorily without any noticeable problem, even with 100% rubber seed oil. A multi-layer artificial neural network model was developed for predicting the performance and emission characteristics of the engine under dual fuel operation. Experimental data has been used to train the network. The predicted engine performance and emission characteristics obtained by neural network model are validated by using the experimental data. The neural network model is found to be quite efficient in predicting engine performance and emission characteristics. It has been found that 60-80% diesel replacement by rubber seed oil is the optimum in order to get maximum engine performance and minimum exhaust emission

  5. Experimental investigation on dual fuel operation of acetylene in a DI diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Lakshmanan, T. [Department of Mechanical Engineering, Rajarajeswari Engineering College, Adayalampattu, Chennai, 600095 (India); Nagarajan, G. [Internal Combustion Engineering Division, College of Engineering, Anna University, Chennai, 600025 (India)

    2010-05-15

    Depletion of fossils fuels and environmental degradation have prompted researchers throughout the world to search for a suitable alternative fuel for diesel engine. One such step is to utilize renewable fuels in diesel engines by partial or total replacement of diesel in dual fuel mode. In this study, acetylene gas has been considered as an alternative fuel for compression ignition engine, which has excellent combustion properties. Investigation has been carried out on a single cylinder, air cooled, direct injection (DI), compression ignition engine designed to develop the rated power output of 4.4 kW at 1500 rpm under variable load conditions, run on dual fuel mode with diesel as injected primary fuel and acetylene inducted as secondary gaseous fuel at various flow rates. Acetylene aspiration resulted in lower thermal efficiency. Smoke, HC and CO emissions reduced, when compared with baseline diesel operation. With acetylene induction, due to high combustion rates, NO{sub x} emission significantly increased. Peak pressure and maximum rate of pressure rise also increased in the dual fuel mode of operation due to higher flame speed. It is concluded that induction of acetylene can significantly reduce smoke, CO and HC emissions with a small penalty on efficiency. (author)

  6. Dual-fuelling of a direct-injection automotive diesel engine by diesel and compressed natural gas

    International Nuclear Information System (INIS)

    Pirouzpanah, V.; Mohammadi Kosha, A.; Mosseibi, A.; Moshirabadi, J.; Gangi, A.; Moghadaspour, M.

    2000-01-01

    Application of Compressed Natural Gas in diesel engines has always been important, especially in the field of automotive engineering. This is due to easy accessibility, better mixing quality and good combustion characteristics of the Compressed Natural Gas fuel. In this study the application of Compressed Natural Gas fuel along with diesel oil in a heavy duty direct-injection automotive diesel engine is experimentally investigated. In order to convert a diesel engine into a diesel-gas one, the so called m ixed diesel-gas a pproach has been used and for this purpose a carbureted Compressed Natural Gas fuel system has been designed and manufactured. For controlling quantity of Compressed Natural Gas, the gas valve is linked to the diesel fuel injection system by means of a set of rods. Then, the dual-fuel system is adjusted so that, at full load conditions, the quantity of diesel fuel is reduced to 20% and 80% of its equivalent energy is substituted by Compressed Natural Gas fuel. Also injection pressure of pilot jet is increased by 11.4%. Performance and emission tests are conducted under variation of load and speed on both diesel and diesel-gas engines. Results show that, with equal power and torque, the diesel-gas engine has the potential to improve overall engine performance and emission. For example, at rated power and speed, fuel economy increases by 5.48%, the amount of smoke decreases by 78%, amount of CO decreases by 64.3% and mean exhaust gas temperature decreases by 6.4%

  7. Modeling and control of fuel distribution in a dual-fuel internal combustion engine leveraging late intake valve closings

    Energy Technology Data Exchange (ETDEWEB)

    Kassa, Mateos [Mechanical, Materials, and Aerospace Engineering Department, Illinois Institute of Technology, Chicago, IL, USA; Hall, Carrie [Mechanical, Materials, and Aerospace Engineering Department, Illinois Institute of Technology, Chicago, IL, USA; Ickes, Andrew [Fuels, Engine and Aftertreatment Research, Argonne National Laboratory, Argonne, IL, USA; Wallner, Thomas [Fuels, Engine and Aftertreatment Research, Argonne National Laboratory, Argonne, IL, USA

    2016-10-07

    Advanced internal combustion engines, although generally more efficient than conventional combustion engines, often encounter limitations in multi-cylinder applications due to variations in the combustion process encountered across cylinders and between cycles. This study leverages experimental data from an inline 6-cylinder heavy-duty dual fuel engine equipped with exhaust gas recirculation (EGR), a variable geometry turbocharger, and a fully-flexible variable intake valve actuation system to study cylinder-to-cylinder variations in power production and the underlying uneven fuel distribution that causes these variations. The engine is operated with late intake valve closure timings in a dual-fuel combustion mode in which a high reactivity fuel is directly injected into the cylinders and a low reactivity fuel is port injected into the cylinders. Both dual fuel implementation and late intake valve closing (IVC) timings have been shown to improve thermal efficiency. However, experimental data from this study reveal that when late IVC timings are used on a multi-cylinder dual fuel engine a significant variation in IMEP across cylinders results and as such, leads to efficiency losses. The difference in IMEP between the different cylinders ranges from 9% at an IVC of 570°ATDC to 38% at an IVC of 610°ATDC and indicates an increasingly uneven fuel distribution. These experimental observations along with engine simulation models developed using GT-Power have been used to better understand the distribution of the port injected fuel across cylinders under various operating conditions on such dual fuel engines. This study revealed that the fuel distribution across cylinders in this dual fuel application is significantly affected by changes in the effective compression ratio as determined by the intake valve close timing as well as the design of the intake system (specifically the length of the intake runners). Late intake valve closures allow a portion of the trapped air

  8. Simultaneous reduction of NO{sub x} and smoke in a dual fuel DI diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Barik, Debabrata; Murugan, S., E-mail: s.murugan@nitrkl.ac.in

    2014-08-01

    Highlights: • A solution to use the de-oiled cakes disposed from oil industries. • Biogas produced from Karanja de-oiled cakes contains about 73% methane. • Simultaneous reduction of NO and smoke is possible with KME–biogas dual fuel operation. • Up to 30% replacement of KME is possible with induction of biogas at 0.9 kg/h. • Improved part load performance and emission with KME–biogas dual fuel. - Abstract: This paper presents the results of an experimental investigation conducted on a compression ignition (CI) engine, modified to run on dual fuel mode, using biogas as a primary fuel and KME (Karanja methyl ester) as a pilot fuel. The biogas was produced by anaerobic digestion of Pongamia pinnata (Karanja) seed cakes. In dual fuel mode, the biogas was inducted at four different flow rates, viz. 0.3 kg/h, 0.6 kg/h, 0.9 kg/h and 1.2 kg/h through the intake manifold of the engine. The biogas flow rate of 0.9 kg/h gave a better performance and lower emissions, than those of the other flow rates. The NO and smoke emissions were found to be lower by about 34% and 14%, than those of KME operation, at full load. The ignition delay was longer by about 1–2 °CA in the dual fuel operation, than that of KME at full load. The part load performance was found to be better in dual fuel operation, with reduced emissions of NO and smoke, in comparison with KME. The ignition delay at part load in dual fuel operation was also lower than that of KME operation.

  9. Simultaneous reduction of NOx and smoke in a dual fuel DI diesel engine

    International Nuclear Information System (INIS)

    Barik, Debabrata; Murugan, S.

    2014-01-01

    Highlights: • A solution to use the de-oiled cakes disposed from oil industries. • Biogas produced from Karanja de-oiled cakes contains about 73% methane. • Simultaneous reduction of NO and smoke is possible with KME–biogas dual fuel operation. • Up to 30% replacement of KME is possible with induction of biogas at 0.9 kg/h. • Improved part load performance and emission with KME–biogas dual fuel. - Abstract: This paper presents the results of an experimental investigation conducted on a compression ignition (CI) engine, modified to run on dual fuel mode, using biogas as a primary fuel and KME (Karanja methyl ester) as a pilot fuel. The biogas was produced by anaerobic digestion of Pongamia pinnata (Karanja) seed cakes. In dual fuel mode, the biogas was inducted at four different flow rates, viz. 0.3 kg/h, 0.6 kg/h, 0.9 kg/h and 1.2 kg/h through the intake manifold of the engine. The biogas flow rate of 0.9 kg/h gave a better performance and lower emissions, than those of the other flow rates. The NO and smoke emissions were found to be lower by about 34% and 14%, than those of KME operation, at full load. The ignition delay was longer by about 1–2 °CA in the dual fuel operation, than that of KME at full load. The part load performance was found to be better in dual fuel operation, with reduced emissions of NO and smoke, in comparison with KME. The ignition delay at part load in dual fuel operation was also lower than that of KME operation

  10. Effect of Biodiesel Fuel Injection Timing and Venture for Gaseous Fuel Induction on the Performance, Emissions and Combustion Characteristics of Dual Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mallikarjun Bhovi

    2018-02-01

    Full Text Available Advancing or retarding pilot fuel injection timing in a diesel engine provided with either conventional mechanical fuel injection (CMFIS or high pressure injection as in common rail fuel injection (CRDI systems can significantly affect its performance and tail pipe emissions. Performance of diesel engine when fueled with various biofuels as well as gaseous fuels tends to vary with subsequent changes in pilot fuel injection timings. Biodiesel derived from rubber seed oil called Rubber Seed Oil Methyl Ester (RuOME and hydrogen (H2 and hydrogen enriched compressed natural gas called (HCNG both being renewable fuels when used in diesel engines modified to operate in dual fuel mode can provide complete replacement for fossil diesel. In the present study, effect of injection timings and venture design for gas mixing on the performance, combustion and emission characteristics of dual fuel engine fitted with both CMFIS and CRDI injection systems and operated on RuOME and HCNG/hydrogen has been investigated. Results showed that high pressure CRDI assisted injection of RuOME with optimized mixing chamber (carburetor for hydrogen induction in dual fuel engine performed improved compared to that with CMFIS. In addition, for the same fuel combinations, CRDI resulted in lower biodiesel consumption, lower carbon monoxide (BSCO and hydrocarbon (BSHC emissions and increased NOx emissions than CMFIS operation.

  11. Effect of engine parameters and gaseous fuel type on the cyclic variability of dual fuel engines

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed Y.E. Selim [United Arab Emirates University, Al-Ain (United Arab Emirates). Mechanical Engineering Department, Faculty of Engineering

    2005-05-01

    This paper presents an analysis of the cycle-to-cycle combustion variation as reflected in the combustion pressure data of a single cylinder, naturally aspirated, four stroke, Ricardo E6 engine converted to run as dual fuel engine on diesel and gaseous fuel of LPG or methane. A measuring set-up consisting of a piezo-electric pressure transducer with charge amplifier and fast data acquisition card installed on an IBM microcomputer was used to gather the data of up to 1200 consecutive combustion cycles of the cylinder under various combination of engine operating and design parameters. These parameters included type of gaseous fuel, engine load, compression ratio, pilot fuel injection timing, pilot fuel mass, and engine speed. The data for each operating conditions were analyzed for the maximum pressure, the maximum rate of pressure rise representing the combustion noise, and indicated mean effective pressure. The cycle-to-cycle variation is expressed as the mean value, standard deviation, and coefficient of variation of these three parameters. It was found that the type of gaseous fuel and engine operating and design parameters affected the combustion noise and its cyclic variation and these effects have been presented. 21 refs., 6 figs., 1 tab.

  12. On Combustion in the CNG-Diesel Dual Fuel Engine

    OpenAIRE

    Königsson, Fredrik

    2014-01-01

    Currently there is a large interest in alternative transport fuels. There are two underlying reasons for this interest: the desire to decrease the environmental impact of transports and the need to compensate for the declining availability of petroleum. In the light of both these factors, the CNG-diesel dual fuelengine is an attractive concept. The primary fuel of the dual fuel engine is methane, which can be derived both from renewables and from fossil sources. Methane from organic waste, co...

  13. LPG diesel dual fuel engine – A critical review

    Directory of Open Access Journals (Sweden)

    B. Ashok

    2015-06-01

    Full Text Available The engine, which uses both conventional diesel fuel and LPG fuel, is referred to as ‘LPG–diesel dual fuel engines’. LPG dual fuel engines are modified diesel engines which use primary fuel as LPG and secondary fuel as diesel. LPG dual fuel engines have a good thermal efficiency at high output but the performance is less during part load conditions due to the poor utilization of charges. This problem can be overcome by varying factors such as pilot fuel quantity, injection timing, composition of the gaseous fuel and intake charge conditions, for improving the performance, combustion and emissions of dual fuel engines. This article reviews about the research work done by the researchers in order to improve the performance, combustion and emission parameters of a LPG–diesel dual fuel engines. From the studies it is shown that the use of LPG in diesel engine is one of the capable methods to reduce the PM and NOx emissions but at same time at part load condition there is a drop in efficiency and power output with respect to diesel operation.

  14. Performance and specific emissions contours throughout the operating range of hydrogen-fueled compression ignition engine with diesel and RME pilot fuels

    Directory of Open Access Journals (Sweden)

    Shahid Imran

    2015-09-01

    Full Text Available This paper presents the performance and emissions contours of a hydrogen dual fueled compression ignition (CI engine with two pilot fuels (diesel and rapeseed methyl ester, and compares the performance and emissions iso-contours of diesel and rapeseed methyl ester (RME single fueling with diesel and RME piloted hydrogen dual fueling throughout the engines operating speed and power range. The collected data have been used to produce iso-contours of thermal efficiency, volumetric efficiency, specific oxides of nitrogen (NOX, specific hydrocarbons (HC and specific carbon dioxide (CO2 on a power-speed plane. The performance and emission maps are experimentally investigated, compared, and critically discussed. Apart from medium loads at lower and medium speeds with diesel piloted hydrogen combustion, dual fueling produced lower thermal efficiency everywhere across the map. For diesel and RME single fueling the maximum specific NOX emissions are centered at the mid speed, mid power region. Hydrogen dual fueling produced higher specific NOX with both pilot fuels as compared to their respective single fueling operations. The range, location and trends of specific NOX varied significantly when compared to single fueling cases. The volumetric efficiency is discussed in detail with the implications of manifold injection of hydrogen analyzed with the conclusions drawn.

  15. One dimensional modeling of a diesel-CNG dual fuel engine

    Science.gov (United States)

    Azman, Putera Adam; Fawzi, Mas; Ismail, Muammar Mukhsin; Osman, Shahrul Azmir

    2017-04-01

    Some of the previous studies have shown that the use of compressed natural gas (CNG) in diesel engines potentially produce engine performance improvement and exhaust gas emission reduction, especially nitrogen oxides, unburned hydrocarbons, and carbon dioxide. On the other hand, there are other researchers who claimed that the use of CNG increases exhaust gas emissions, particularly nitrogen oxides. In this study, a one-dimensional model of a diesel-CNG dual fuel engine was made based on a 4-cylinder 2.5L common rail direct injection diesel engine. The software used is GT-Power, and it was used to analyze the engine performance and exhaust gas emissions of several diesel-CNG dual fuel blend ratios, i.e. 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50. The effect of 100%, 75%, 50% engine loads on the exhaust gas emissions were also studied. The result shows that all diesel-CNG fuel blends produces higher brake torque and brake power at engine speed of 2000-3000 rpm compared with 100% diesel. The 50:50 diesel-CNG blend produces the highest brake torque and brake power, but also has the highest brake specific fuel consumption. As a higher percentage of CNG added to the dual fuel blend, unburned hydrocarbons and carbon monoxide emission increased while carbon dioxide emission decreased. The nitrogen oxides emission concentration is generally unaffected by any change of the dual fuel ratio.

  16. Advancing the Limits of Dual Fuel Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Koenigsson, Fredrik

    2012-07-01

    There is a growing interest in alternative transport fuels. There are two underlying reasons for this interest; the desire to decrease the environmental impact of transports and the need to compensate for the declining availability of petroleum. In the light of both these factors the Diesel Dual Fuel, DDF, engine is an attractive concept. The primary fuel of the DDF engine is methane, which can be derived both from renewables and from fossil sources. Methane from organic waste; commonly referred to as biomethane, can provide a reduction in greenhouse gases unmatched by any other fuel. The DDF engine is from a combustion point of view a hybrid between the diesel and the otto engine and it shares characteristics with both. This work identifies the main challenges of DDF operation and suggests methods to overcome them. Injector tip temperature and pre-ignitions have been found to limit performance in addition to the restrictions known from literature such as knock and emissions of NO{sub x} and HC. HC emissions are especially challenging at light load where throttling is required to promote flame propagation. For this reason it is desired to increase the lean limit in the light load range in order to reduce pumping losses and increase efficiency. It is shown that the best results in this area are achieved by using early diesel injection to achieve HCCI/RCCI combustion where combustion phasing is controlled by the ratio between diesel and methane. However, even without committing to HCCI/RCCI combustion and the difficult control issues associated with it, substantial gains are accomplished by splitting the diesel injection into two and allocating most of the diesel fuel to the early injection. HCCI/RCCI and PPCI combustion can be used with great effect to reduce the emissions of unburned hydrocarbons at light load. At high load, the challenges that need to be overcome are mostly related to heat. Injector tip temperatures need to be observed since the cooling effect of

  17. Standardized Gasoline Compression Ignition Fuels Matrix

    KAUST Repository

    Badra, Jihad

    2018-04-03

    Direct injection compression ignition engines running on gasoline-like fuels have been considered an attractive alternative to traditional spark ignition and diesel engines. The compression and lean combustion mode eliminates throttle losses yielding higher thermodynamic efficiencies and the better mixing of fuel/air due to the longer ignition delay times of the gasoline-like fuels allows better emission performance such as nitric oxides (NOx) and particulate matter (PM). These gasoline-like fuels which usually have lower octane compared to market gasoline have been identified as a viable option for the gasoline compression ignition (GCI) engine applications due to its lower reactivity and lighter evaporation compared to diesel. The properties, specifications and sources of these GCI fuels are not fully understood yet because this technology is relatively new. In this work, a GCI fuel matrix is being developed based on the significance of certain physical and chemical properties in GCI engine operation. Those properties were chosen to be density, temperature at 90 volume % evaporation (T90) or final boiling point (FBP) and research octane number (RON) and the ranges of these properties were determined from the data reported in literature. These proposed fuels were theoretically formulated, while applying realistic constraints, using species present in real refinery streams. Finally, three-dimensional (3D) engine computational fluid dynamics (CFD) simulations were performed using the proposed GCI fuels and the similarities and differences were highlighted.

  18. Standardized Gasoline Compression Ignition Fuels Matrix

    KAUST Repository

    Badra, Jihad; Bakor, Radwan; AlRamadan, Abdullah; Almansour, Mohammed; Sim, Jaeheon; Ahmed, Ahfaz; Viollet, Yoann; Chang, Junseok

    2018-01-01

    Direct injection compression ignition engines running on gasoline-like fuels have been considered an attractive alternative to traditional spark ignition and diesel engines. The compression and lean combustion mode eliminates throttle losses yielding higher thermodynamic efficiencies and the better mixing of fuel/air due to the longer ignition delay times of the gasoline-like fuels allows better emission performance such as nitric oxides (NOx) and particulate matter (PM). These gasoline-like fuels which usually have lower octane compared to market gasoline have been identified as a viable option for the gasoline compression ignition (GCI) engine applications due to its lower reactivity and lighter evaporation compared to diesel. The properties, specifications and sources of these GCI fuels are not fully understood yet because this technology is relatively new. In this work, a GCI fuel matrix is being developed based on the significance of certain physical and chemical properties in GCI engine operation. Those properties were chosen to be density, temperature at 90 volume % evaporation (T90) or final boiling point (FBP) and research octane number (RON) and the ranges of these properties were determined from the data reported in literature. These proposed fuels were theoretically formulated, while applying realistic constraints, using species present in real refinery streams. Finally, three-dimensional (3D) engine computational fluid dynamics (CFD) simulations were performed using the proposed GCI fuels and the similarities and differences were highlighted.

  19. Effect of compressive force on PEM fuel cell performance

    Science.gov (United States)

    MacDonald, Colin Stephen

    Polymer electrolyte membrane (PEM) fuel cells possess the potential, as a zero-emission power source, to replace the internal combustion engine as the primary option for transportation applications. Though there are a number of obstacles to vast PEM fuel cell commercialization, such as high cost and limited durability, there has been significant progress in the field to achieve this goal. Experimental testing and analysis of fuel cell performance has been an important tool in this advancement. Experimental studies of the PEM fuel cell not only identify unfiltered performance response to manipulation of variables, but also aid in the advancement of fuel cell modelling, by allowing for validation of computational schemes. Compressive force used to contain a fuel cell assembly can play a significant role in how effectively the cell functions, the most obvious example being to ensure proper sealing within the cell. Compression can have a considerable impact on cell performance beyond the sealing aspects. The force can manipulate the ability to deliver reactants and the electrochemical functions of the cell, by altering the layers in the cell susceptible to this force. For these reasons an experimental study was undertaken, presented in this thesis, with specific focus placed on cell compression; in order to study its effect on reactant flow fields and performance response. The goal of the thesis was to develop a consistent and accurate general test procedure for the experimental analysis of a PEM fuel cell in order to analyse the effects of compression on performance. The factors potentially affecting cell performance, which were a function of compression, were identified as: (1) Sealing and surface contact; (2) Pressure drop across the flow channel; (3) Porosity of the GDL. Each factor was analysed independently in order to determine the individual contribution to changes in performance. An optimal degree of compression was identified for the cell configuration in

  20. A study on an electronically controlled liquefied petroleum gas diesel dual-fuel automobile

    Energy Technology Data Exchange (ETDEWEB)

    Chunhua Zhang; Yaozhang Bian; Lizeng Si; Junzhi Liao; Odbileg, N. [Chang' an Univ., Automobile Faculty, Xi' an (China)

    2005-02-15

    In this paper, the control scheme of a liquefied petroleum gas (LPG)-diesel dual-fuel engine with electronic control is illustrated, the external characteristics and load characteristics of the LPG-diesel dual-fuel engine and the diesel engine are compared and analysed, and the results of automobile road tests are also given. The experimental results show that, compared with diesel, the output performance of dual fuel is not reduced, while smoke emission of dual fuel is significantly reduced, NO{sub x} emission of dual fuel is hardly changed, but HC emission and CO emission of dual fuel are increased and fuel consumption of dual fuel is reduced. (Author)

  1. Apparatus and method for grounding compressed fuel fueling operator

    Science.gov (United States)

    Cohen, Joseph Perry; Farese, David John; Xu, Jianguo

    2002-06-11

    A safety system for grounding an operator at a fueling station prior to removing a fuel fill nozzle from a fuel tank upon completion of a fuel filling operation is provided which includes a fuel tank port in communication with the fuel tank for receiving and retaining the nozzle during the fuel filling operation and a grounding device adjacent to the fuel tank port which includes a grounding switch having a contact member that receives physical contact by the operator and where physical contact of the contact member activates the grounding switch. A releasable interlock is included that provides a lock position wherein the nozzle is locked into the port upon insertion of the nozzle into the port and a release position wherein the nozzle is releasable from the port upon completion of the fuel filling operation and after physical contact of the contact member is accomplished.

  2. Hydrogen as an Auxiliary Fuel in Compression-Ignition Engines

    Science.gov (United States)

    Gerrish, Harold C; Foster, H

    1936-01-01

    An investigation was made to determine whether a sufficient amount of hydrogen could be efficiently burned in a compression-ignition engine to compensate for the increase of lift of an airship due to the consumption of the fuel oil. The performance of a single-cylinder four-stroke-cycle compression-ignition engine operating on fuel oil alone was compared with its performance when various quantities of hydrogen were inducted with the inlet air. Engine-performance data, indicator cards, and exhaust-gas samples were obtained for each change in engine-operating conditions.

  3. Effect of engine parameters and type of gaseous fuel on the performance of dual-fuel gas diesel engines. A critical review

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, B.B. [Centre for Energy, Indian Institute of Technology, Guwahati 781039 (India); Sahoo, N.; Saha, U.K. [Department of Mechanical Engineering, Indian Institute of Technology, Guwahati 781039 (India)

    2009-08-15

    Petroleum resources are finite and, therefore, search for their alternative non-petroleum fuels for internal combustion engines is continuing all over the world. Moreover gases emitted by petroleum fuel driven vehicles have an adverse effect on the environment and human health. There is universal acceptance of the need to reduce such emissions. Towards this, scientists have proposed various solutions for diesel engines, one of which is the use of gaseous fuels as a supplement for liquid diesel fuel. These engines, which use conventional diesel fuel and gaseous fuel, are referred to as 'dual-fuel engines'. Natural gas and bio-derived gas appear more attractive alternative fuels for dual-fuel engines in view of their friendly environmental nature. In the gas-fumigated dual-fuel engine, the primary fuel is mixed outside the cylinder before it is inducted into the cylinder. A pilot quantity of liquid fuel is injected towards the end of the compression stroke to initiate combustion. When considering a gaseous fuel for use in existing diesel engines, a number of issues which include, the effects of engine operating and design parameters, and type of gaseous fuel, on the performance of the dual-fuel engines, are important. This paper reviews the research on above issues carried out by various scientists in different diesel engines. This paper touches upon performance, combustion and emission characteristics of dual-fuel engines which use natural gas, biogas, producer gas, methane, liquefied petroleum gas, propane, etc. as gaseous fuel. It reveals that 'dual-fuel concept' is a promising technique for controlling both NO{sub x} and soot emissions even on existing diesel engine. But, HC, CO emissions and 'bsfc' are higher for part load gas diesel engine operations. Thermal efficiency of dual-fuel engines improve either with increased engine speed, or with advanced injection timings, or with increased amount of pilot fuel. The ignition

  4. Development of design technology for dual-cooled fuel

    International Nuclear Information System (INIS)

    Kim, Hyung Kyu; Yoon, Kyung Ho; Lee, Young Ho

    2010-03-01

    Primary purpose of the project is to complete a basic design of the power uprating dual-cooled fuel's structural components for an actual use in the existing nuclear power plants. It also includes a basic design of the components of a dual-cooled fuel rod. To this end, during the three years of the first stage (2007.03.∼2010.02.), concepts and technical issues of the structural components such as a supporting structure, guide thimbles and instrumentation tube and the top and bottom end pieces were derived in order to comply with the functional requirements and design criteria of them. Basic design was carried out to resolve the issues by using analytical methods as well as experiments, and observed finally is that a structural compatibility of the designed dual-cooled fuel to the Korean Standard Nuclear Power Plant (OPR-1000). As for the dual-cooled fuel rod's components such as a plenum spring, a spacer and end plugs, a concept of them was established by using the basic dimension and array produced by other sub-projects. In turn, the basic design was completed by using the finite element analysis and conventional mechanical design formulae. Additionally, a welding method and equipment for a dual-cooled fuel rod specimen was also successfully developed to prepare for the irradiation tests at the HANARO. It was shown that a dual-cooed fuel for the OPR-1000 can be designed after manufacturing the partial assembly with the designed components and their drawings. The first stage was completed with passing the Gate checks proposed at the beginning. During the second stage(2010.03.∼2012.02.), researches on the mechanical behavior and structural integrity of the designed dual-cooled fuel will be conducted for preparing a license of it, which should be done when the dual-cooled fuel is commercialized

  5. Optimal dual-fuel propulsion for minimum inert weight or minimum fuel cost

    Science.gov (United States)

    Martin, J. A.

    1973-01-01

    An analytical investigation of single-stage vehicles with multiple propulsion phases has been conducted with the phasing optimized to minimize a general cost function. Some results are presented for linearized sizing relationships which indicate that single-stage-to-orbit, dual-fuel rocket vehicles can have lower inert weight than similar single-fuel rocket vehicles and that the advantage of dual-fuel vehicles can be increased if a dual-fuel engine is developed. The results also indicate that the optimum split can vary considerably with the choice of cost function to be minimized.

  6. Evaluation of the performance of a dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Toshiharu [The Japan Gas Association, Tokyo (Japan). NGV Project Dept.; Daisho, Yasuhiro; Saito, Takeshi [Waseda Univ., Tokyo (Japan)

    1998-12-31

    Dual fuel operation, in which natural gas is mixed with the diesel engine intake air and ignition is by diesel fuel spray, has the advantage that engine conversion is simple. Under high load it has the same high efficiency as a diesel engine and it can be switched to normal diesel operation for long distance running. Also, NO{sub x} and black smoke emissions can also be reduced. However, the disadvantages are to increase HC and CO emissions, to reduce efficiency under low load, and to emit the large amount of NO{sub x} under high load. Waseda University was commissioned by Tokyo Gas Co., Ltd. to conduct research program involving experimentation ragarding a dual fuel engine. It was then discovered that the most effective means of solving the problems mentioned above is Exhaust Gas Recirculation (EGR) and that the effect can be increased by heating the intake air. An old engine before the current emission standard was converted to dual fuel operation. It was found that these measures enables NO{sub x}, black smoke and CO{sub 2} to be reduced while high thermal efficiency was maintained. They did not reach the point of satisfying latest Japanese emission standard. But it seemed that good results would have been obtained, if a base engine with good emissions had been converted for dual fuel operation. The results of assessing the performance of the dual fuel engine at this time are reported here, centered on the effect of EGR and intake heating. (orig.)

  7. Dual-fuel HCCI operation with DME/LPG/gasoline/hydrogen

    International Nuclear Information System (INIS)

    Bae, C.

    2009-01-01

    The advantages of homogeneous charge compression ignition (HCCI) engines include usage of the different type of fuels, ultra low nitrogen oxide and particulate matter emissions and improved fuel economy. Disadvantages include an excessive combustion rate, engine noise, and hydrocarbon and carbon emissions. An experiment on dual-fuel HCCI operation with dimethyl ether (DME)/liquefied petroleum gas (LPG)/gasoline/hydrogen was presented. The advantages and disadvantages were first presented and the dual-fuel HCCI combustion engine was illustrated through an experimental apparatus. The experimental conditions were also presented in terms of engine speed, DME injection quantity, LPC injection quantity, and LPC composition. Experimental results were discussed for output performance and indicated mean effective pressure (IMEP). It was concluded that the effect of LPG composition in a DME-LPG dual-fueled HCCI engine at various injection quantity and injective timing were observed. Specifically, it was found that propane was a more effective way to increase IMEP in this study, and that in a DME HCCI engine, higher load limit was extended by using LPG as an ignition inhibitor. tabs., figs.

  8. High temperature compression tests performed on doped fuels

    Energy Technology Data Exchange (ETDEWEB)

    Duguay, C.; Mocellin, A.; Dehaudt, P. [Commissariat a l`Energie Atomique, CEA Grenoble (France); Fantozzi, G. [INSA Lyon - GEMPPM, Villeurbanne (France)

    1997-12-31

    The use of additives of corundum structure M{sub 2}O{sub 3} (M=Cr, Al) is an effective way of promoting grain growth of uranium dioxide. The high-temperature compressive deformation of large-grained UO{sub 2} doped with these oxides has been investigated and compared with that of pure UO{sub 2} with a standard microstructure. Such doped fuels are expected to exhibit enhanced plasticity. Their use would therefore reduce the pellet-cladding mechanical interaction and thus improve the performances of the nuclear fuel. (orig.) 5 refs.

  9. High temperature compression tests performed on doped fuels

    International Nuclear Information System (INIS)

    Duguay, C.; Mocellin, A.; Dehaudt, P.; Fantozzi, G.

    1997-01-01

    The use of additives of corundum structure M 2 O 3 (M=Cr, Al) is an effective way of promoting grain growth of uranium dioxide. The high-temperature compressive deformation of large-grained UO 2 doped with these oxides has been investigated and compared with that of pure UO 2 with a standard microstructure. Such doped fuels are expected to exhibit enhanced plasticity. Their use would therefore reduce the pellet-cladding mechanical interaction and thus improve the performances of the nuclear fuel. (orig.)

  10. Main conditions and effectiveness of gas fuel use for powering of dual fuel IC self-ignition engine

    Directory of Open Access Journals (Sweden)

    Stefan POSTRZEDNIK

    2015-09-01

    Full Text Available Internal combustion engines are fuelled mostly with liquid fuels (gasoline, diesel. Nowadays the gaseous fuels are applied as driving fuel of combustion engines. In case of spark ignition engines the liquid fuel (petrol can be totally replaced by the gas fuels. This possibility in case of compression engines is essentially restricted through the higher self-ignition temperatures of the combustible gases in comparison to classical diesel oil. Solution if this problem can be achieved by using of the dual fuel system, where for ignition of the prepared fuel gas - air mixture a specified amount of the liquid fuel (diesel oil should be additionally injected into the combustion chamber. For assurance that the combustion process proceeds without mistakes and completely, some basic conditions should be satisfied. In the frame of this work, three main aspects of this problem are taken into account: a. filling efficiency of the engine, b. stoichiometry of the combustion, c. performance of mechanical parameters (torque, power. A complex analysis of these conditions has been done and some achieved important results are presented in the paper.

  11. Conceptual Design of Structural Components of a Dual Cooled Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung-Kyu; Lee, Young-Ho; Lee, Kang-Hee; Kim, Jae-Yong; Yoon, Kyung-Ho

    2008-01-15

    A dual cooled fuel, featured by an internal as well as an external coolant flow passage of a fuel rod, was suggested to enable a large-scaled power-uprate of PWR plant and launched as one of the National Nuclear R and D Projects in 2007. It is necessary to make the dual cooled fuel be compatible with an OPR-1000 system to maximize the economy. Also, the structural components of the dual cooled fuel should be designed to realize their features. To this end, a conceptual design of a spacer grid, outer and center guide tubes, and top and bottom end pieces has been carried out in the project 'Development of Design Technology for Dual Cooled Fuel Structure'. For the spacer grids, it is suggested that springs and dimples are located at or near the cross points of the straps due to a considerably narrowed rod-to-rod gap. Candidate shapes of the grids were also developed and applied for domestic patents. For the outer and center guide tubes, a dual tube like a fuel rod was suggested to make the subchannel areas around the guide tubes be similar to those around the fuel rods of enlarged diameter. It was applied for the domestic patent as well. For the top and bottom end pieces, the shape and pattern have been changed from the conventional ones reflecting the fuel rods' changes. Technical issues and method of resolution for each components were listed up for a basic design works in the following years.

  12. Performance and emissions of a dual-fuel pilot diesel ignition engine operating on various premixed fuels

    International Nuclear Information System (INIS)

    Yousefi, Amin; Birouk, Madjid; Lawler, Benjamin; Gharehghani, Ayatallah

    2015-01-01

    Highlights: • Natural gas/diesel, methanol/diesel, and hydrogen/diesel cases were investigated. • For leaner mixtures, the hydrogen/diesel case has the highest IMEP and ITE. • The methanol/diesel case has the maximum IMEP and ITE for richer mixtures. • Hydrogen/diesel case experiences soot and CO free combustion at rich regions. - Abstract: A multi-dimensional computational fluid dynamics (CFD) model coupled with chemical kinetics mechanisms was applied to investigate the effect of various premixed fuels and equivalence ratios on the combustion, performance, and emissions characteristics of a dual-fuel indirect injection (IDI) pilot diesel ignition engine. The diesel fuel is supplied via indirect injection into the cylinder prior to the end of the compression stroke. Various premixed fuels were inducted into the engine through the intake manifold. The results showed that the dual-fuel case using hydrogen/diesel has a steeper pressure rise rate, higher peak heat release rate (PHRR), more advanced ignition timing, and shorter ignition delay compared to the natural gas/diesel and methanol/diesel dual-fuel cases. For leaner mixtures (Φ_P 0.32). For instance, with an equivalence ratio of 0.35, the ITE is 56.24% and 60.85% for hydrogen/diesel and methanol/diesel dual-fuel cases, respectively. For an equivalence ratio of 0.15, the natural gas/diesel simulation exhibits partial burn combustion and thus results in a negative IMEP. At equivalence ratios of 0.15, 0.2, and 0.25, the methanol/diesel case experiences misfiring phenomenon which consequently deteriorates the engine performance considerably. As for the engine-out emissions, the hydrogen/diesel results display carbon monoxide (CO) free combustion relative to natural gas/diesel and methanol/diesel engines; however, considerable amount of nitrogen oxides (NO_x) emissions are produced at an equivalence ratio of 0.35 which exceeds the Euro 6 NO_x limit. Due to the larger area exposed to high temperature regions

  13. Fundamental Interactions in Gasoline Compression Ignition Engines with Fuel Stratification

    Science.gov (United States)

    Wolk, Benjamin Matthew

    Transportation accounted for 28% of the total U.S. energy demand in 2011, with 93% of U.S. transportation energy coming from petroleum. The large impact of the transportation sector on global climate change necessitates more-efficient, cleaner-burning internal combustion engine operating strategies. One such strategy that has received substantial research attention in the last decade is Homogeneous Charge Compression Ignition (HCCI). Although the efficiency and emissions benefits of HCCI are well established, practical limits on the operating range of HCCI engines have inhibited their application in consumer vehicles. One such limit is at high load, where the pressure rise rate in the combustion chamber becomes excessively large. Fuel stratification is a potential strategy for reducing the maximum pressure rise rate in HCCI engines. The aim is to introduce reactivity gradients through fuel stratification to promote sequential auto-ignition rather than a bulk-ignition, as in the homogeneous case. A gasoline-fueled compression ignition engine with fuel stratification is termed a Gasoline Compression Ignition (GCI) engine. Although a reasonable amount of experimental research has been performed for fuel stratification in GCI engines, a clear understanding of how the fundamental in-cylinder processes of fuel spray evaporation, mixing, and heat release contribute to the observed phenomena is lacking. Of particular interest is gasoline's pressure sensitive low-temperature chemistry and how it impacts the sequential auto-ignition of the stratified charge. In order to computationally study GCI with fuel stratification using three-dimensional computational fluid dynamics (CFD) and chemical kinetics, two reduced mechanisms have been developed. The reduced mechanisms were developed from a large, detailed mechanism with about 1400 species for a 4-component gasoline surrogate. The two versions of the reduced mechanism developed in this work are: (1) a 96-species version and (2

  14. A Priori Analysis of a Compressible Flamelet Model using RANS Data for a Dual-Mode Scramjet Combustor

    Science.gov (United States)

    Quinlan, Jesse R.; Drozda, Tomasz G.; McDaniel, James C.; Lacaze, Guilhem; Oefelein, Joseph

    2015-01-01

    In an effort to make large eddy simulation of hydrocarbon-fueled scramjet combustors more computationally accessible using realistic chemical reaction mechanisms, a compressible flamelet/progress variable (FPV) model was proposed that extends current FPV model formulations to high-speed, compressible flows. Development of this model relied on observations garnered from an a priori analysis of the Reynolds-Averaged Navier-Stokes (RANS) data obtained for the Hypersonic International Flight Research and Experimentation (HI-FiRE) dual-mode scramjet combustor. The RANS data were obtained using a reduced chemical mechanism for the combustion of a JP-7 surrogate and were validated using avail- able experimental data. These RANS data were then post-processed to obtain, in an a priori fashion, the scalar fields corresponding to an FPV-based modeling approach. In the current work, in addition to the proposed compressible flamelet model, a standard incompressible FPV model was also considered. Several candidate progress variables were investigated for their ability to recover static temperature and major and minor product species. The effects of pressure and temperature on the tabulated progress variable source term were characterized, and model coupling terms embedded in the Reynolds- averaged Navier-Stokes equations were studied. Finally, results for the novel compressible flamelet/progress variable model were presented to demonstrate the improvement attained by modeling the effects of pressure and flamelet boundary conditions on the combustion.

  15. 49 CFR 571.303 - Standard No. 303; Fuel system integrity of compressed natural gas vehicles.

    Science.gov (United States)

    2010-10-01

    ... compressed natural gas vehicles. 571.303 Section 571.303 Transportation Other Regulations Relating to... system integrity of compressed natural gas vehicles. S1. Scope. This standard specifies requirements for the integrity of motor vehicle fuel systems using compressed natural gas (CNG), including the CNG fuel...

  16. Dual-fuel engine with cylinder pressure based control

    Energy Technology Data Exchange (ETDEWEB)

    Ritscher, Bert [Caterpillar Motoren GmbH und Co. KG, Kiel (Germany). Large Power Systems Div.

    2013-10-15

    Cylinder pressure sensors were initially used to detect knocking and misfiring on spark ignited gas engines. On its latest MaK brand dual-fuel engine, Caterpillar Motoren is harnessing the deep insights into combustion and engine condition that can be derived direct from the origin of engine power in sophisticated control, monitoring and diagnostic systems. (orig.)

  17. Tamanu oil. An alternative fuel for variable compression ratio engine

    Energy Technology Data Exchange (ETDEWEB)

    Raj, Mohan T. [SASTRA Univ., Thanjavur, Tamilnadu (India). Dept. of Mechanical Engineering; Kandasamy, Murugumohan Kumar K. [Pavendar Bharathidasan College of Engineering and Technology, Trichy, Tamilnadu (India). Dept. of Mechanical Engineering

    2012-11-01

    Biodiesel can be produced from vegetable oils and also from waste fats. Biodiesel is a monoalkyl- ester of long chain fatty acids derived from renewable feedstock such as vegetable oils by transesterification process. The esterified cotton seed oil, pungam oil, rice bran oil, and tamanu oil are chosen as the alternative fuels. Among these oils, tamanu oil is considered for the first time as an alternative fuel. An experiment is conducted to obtain the operating characteristics of the variable compression ratio (VCR) engine run by chosen esterified oils, and the results are compared with esterified tamanu oil. From the comparison of results, it is inferred that the engine performance is improved with significant reduction in emissions for the chosen oils without any engine modification. The effective compression ratio can be fixed based on the experimental results obtained in the engine since the findings of the present research work infer that the biodiesel obtained from tamanu oil is a promising alternative fuel for direct-injection four-stroke VCR engine. (orig.)

  18. Experimental study of dual fuel engine performance using variable LPG composition and engine parameters

    International Nuclear Information System (INIS)

    Elnajjar, Emad; Selim, Mohamed Y.E.; Hamdan, Mohammad O.

    2013-01-01

    Highlights: • The effect of using variable LPG is studied. • Five fuels with propane to butane % volume ratio are: 100-70-55-25-0. • 100% Propane composition shows the highest noise levels with similar performance. • At 45° BTDC injection timing 55% Propane LPG the only fuel experience knocking. • LPG fuels gave similar engine performance, with differences in levels of noise. - Abstract: The present work investigates experimentally the effect of LPG fuel with different composition and engine parameters on the performance of a dual compression engine. Five different blends of LPG fuels are used with Propane to Butane volume ratio of 100:0, 70:30, 55:45, 25:75, and 0:100. A single cylinder, naturally aspirated, four strokes, indirectly injected, water cooled modified Ricardo E6 engine, is used in this study. The study is carried out by measuring the cylinder pressure, engine load, engine speed, crank angle, and the fuel’s flow rate. The engine performance under variable LPG fuel composition, engine load, pilot fuel injection timing, compression ratio, pilot fuel mass and engine speed, are estimated by comparing the following engine parameters: the cylinder maximum pressure, the indicated mean effective pressure, the maximum rate of pressure rise, and the thermal efficiency. The experimental data indicates that the engine parameters are playing a major role on the engine’s performance. Different LPG fuel composition did not show a major effect on the engine efficiency but directly impacted the levels of generated combustion noise

  19. CNG INJECTOR RESEARCH FOR DUAL FUEL ENGINE

    Directory of Open Access Journals (Sweden)

    Adam Majczak

    2017-03-01

    Full Text Available The article presents the tests results of the prototype design of hydraulically assisted injector, that is designed for gas supply into diesel engines. The construction of the injector allows for it positioning in the glow plug socket, so that the gas is injected directly into the combustion chamber. The cycle analysis of the four-cylinder Andoria ADCR engine with a capacity of 2.6 dm3 for different crankshaft rotational speeds allowed to determine the necessary time for fuel injection. Because of that, it was possible to determine the required mass flow rate of the injector, for replacing as much of the original fuel by gaseous fuel. To ensure a high value of flow inside the injector, supply pressure equal to 1 MPa was applied. High gas supply pressure requires high value of valve opening forces. For this purpose a injector with hydraulic control system, using a liquid under pressure for the opening process was designed. On the basis of air pressure measurements in the flow line after the injector, the analysis of opening and closing of the valve was made. Measurements of outflow mass of the injector were also carried out. The results showed that the designed injector meets the requirements necessary to supply ADCR engine by the CNG fuel.

  20. Near-optimal operation of dual-fuel launch vehicles

    International Nuclear Information System (INIS)

    Ardema, M.D.; Chou, H.C.; Bowles, J.V.

    1994-01-01

    Current studies of single-stage-to-orbit (SSTO) launch vehicles are focused on all-rocket propulsion systems. One option for such vehicles is the use of dual-fuel (liquid hydrocarbon and liquid hydrogen (LH 2 )), for a portion of the mission. As compared with LH 2 , hydrocarbon fuel has higher density and produces higher thrust-to-weight, but has lower specific impulse. The advantages of hydrocarbon fuel are important early in the ascent trajectory, and its use may be expected to lead to reduced vehicle size and weight. Because LH 2 is also needed for cooling purposes, in the early portion of the trajectory both fuels must be burned simultaneously. Later in the ascent, when vehicle weight is lower, specific impulse is the key parameter, indicating single-fuel LH 2 use

  1. Compressed Natural Gas Technology for Alternative Fuel Power Plants

    Science.gov (United States)

    Pujotomo, Isworo

    2018-02-01

    Gas has great potential to be converted into electrical energy. Indonesia has natural gas reserves up to 50 years in the future, but the optimization of the gas to be converted into electricity is low and unable to compete with coal. Gas is converted into electricity has low electrical efficiency (25%), and the raw materials are more expensive than coal. Steam from a lot of wasted gas turbine, thus the need for utilizing exhaust gas results from gas turbine units. Combined cycle technology (Gas and Steam Power Plant) be a solution to improve the efficiency of electricity. Among other Thermal Units, Steam Power Plant (Combined Cycle Power Plant) has a high electrical efficiency (45%). Weakness of the current Gas and Steam Power Plant peak burden still using fuel oil. Compressed Natural Gas (CNG) Technology may be used to accommodate the gas with little land use. CNG gas stored in the circumstances of great pressure up to 250 bar, in contrast to gas directly converted into electricity in a power plant only 27 bar pressure. Stored in CNG gas used as a fuel to replace load bearing peak. Lawyer System on CNG conversion as well as the power plant is generally only used compressed gas with greater pressure and a bit of land.

  2. Optimization of combustion chamber geometry and operating conditions for compression ignition engine fueled with pre-blended gasoline-diesel fuel

    International Nuclear Information System (INIS)

    Lee, Seokhwon; Jeon, Joonho; Park, Sungwook

    2016-01-01

    Highlights: • Pre-blended gasoline-diesel fuel was used with direct injection system. • KIVA-CHEMKIN code modeled dual-fuel fuel spray and combustion processes with discrete multi-component model. • The characteristics of Combustion and emission on pre-blended fuel was investigated with various fuel reactivities. • Optimization of combustion chamber shape improved combustion performance of the gasoline-diesel blended fuel engine. - Abstract: In this study, experiments and numerical simulations were used to improve the fuel efficiency of compression ignition engine using a gasoline-diesel blended fuel and an optimization technology. The blended fuel is directly injected into the cylinder with various blending ratios. Combustion and emission characteristics were investigated to explore the effects of gasoline ratio on fuel blend. The present study showed that the advantages of gasoline-diesel blended fuel, high thermal efficiency and low emission, were maximized using the numerical optimization method. The ignition delay and maximum pressure rise rate increased with the proportion of gasoline. As the gasoline fraction increased, the combustion duration and the indicated mean effective pressure decreased. The homogeneity of the fuel-air mixture was improved due to longer ignition delay. Soot emission was significantly reduced up to 90% compared to that of conventional diesel. The nitrogen oxides emissions of the blended fuel increased slightly when the start of injection was retarded toward top dead center. For the numerical study, KIVA-CHEMKIN multi-dimensional CFD code was used to model the combustion and emission characteristics of gasoline-diesel blended fuel. The micro genetic algorithm coupled with the KIVA-CHEMKIN code were used to optimize the combustion chamber shape and operating conditions to improve the combustion performance of the blended fuel engine. The optimized chamber geometry enhanced the fuel efficiency, for a level of nitrogen oxides

  3. Application of jatropha oil and biogas in a dual fuel engine for rural electrification

    Energy Technology Data Exchange (ETDEWEB)

    Kerkhof, E.

    2008-06-15

    a 10 kW load; thermal efficiency did not deteriorate up to 70% heat release fraction of methane. At 6 kW and 8 kW, thermal efficiency decreases with increasing heat release fraction from methane. The decrease is in the order of 5% to 10% of the initial efficiency. For dual fuel operation with pure methane thermal efficiency even decreased at a 10 kW load. Volumetric efficiency and air-excess ratio decreased under dual fuel operation as expected. The decrease did not result in a deficiency of oxygen. Enough oxygen was available to combust oil smoke-free. The amount of carbon dioxide in the biogas did not influence performance parameters; the smoke limit was not reached. The engine runs without problems up to a heat release fraction of 60% methane. Between 60% and 70% irregularities are observed. The irregularities are attributed to light end-gas knock. Therefore, it is advised against, to replace a larger part of the fuel by biogas. A different engine design (i.e. different compression ratio) might be able to operate without problems with more biogas in the fuel mixture. For a better understanding more research is required; heat release should be measured with an incylinder pressure measurement; this would give a better insight into changes in thermal efficiency and operation limits. It is possible to use a diesel engine to generate electricity with jatropha oil and biogas as fuels. The technologies used in the experimental set-up are low-tech and locally available; therefore it is considered an appropriate technology for the use in rural areas in developing countries.

  4. Physical and chemical effects of low octane gasoline fuels on compression ignition combustion

    KAUST Repository

    Badra, Jihad; Viollet, Yoann; Elwardani, Ahmed Elsaid; Im, Hong G.; Chang, Junseok

    2016-01-01

    Gasoline compression ignition (GCI) engines running on low octane gasoline fuels are considered an attractive alternative to traditional spark ignition engines. In this study, three fuels with different chemical and physical characteristics have

  5. Numerical Studies on Controlling Gaseous Fuel Combustion by Managing the Combustion Process of Diesel Pilot Dose in a Dual-Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mikulski Maciej

    2015-06-01

    Full Text Available Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.

  6. Fuels for homogeneous charge compression ignition (HCCI) engines. Automotive fuels survey. Part 6

    Energy Technology Data Exchange (ETDEWEB)

    Van Walwijk, M.

    2001-01-01

    Homogeneous charge compression ignition (HCCI) is a third mode of operation for internal combustion engines, beside spark ignition and conventional compression ignition. This report concentrates on the requirements that HCCI operation puts on fuels for these engines. For readers with limited time available, this summary describes the main findings. Policy makers that need some more background information may turn directly to chapter 7, 'Fuels for HCCI engines'. The rest of this report can be considered as a reference guide for more detailed information. The driving force to investigate HCCI engines is the potential of low emissions and simultaneously high energy efficiency. HCCI is gaining attention the last few years. However, HCCI engines are still in the research phase. After many experiments with prototype engines, people have now started working on computer simulations of the combustion process, to obtain a fundamental understanding of HCCI combustion and to steer future engine developments. In HCCI engines, an air/fuel mixture is prepared before it enters the combustion chamber. The homogeneous mixture is in the combustion chamber compressed to auto-ignition. Unlike in conventional engines, combustion starts at many different locations simultaneously and the speed of combustion is very high, so there is no flame front. Lean air/fuel mixtures (excess air) are used to control combustion speed. Because of the excess air, combustion temperature is relatively low, resulting in low NOx emissions. When the fuel is vaporised to a truly homogeneous mixture, complete combustion results in low particulate emissions. The most important advantages of HCCI engines are: - Emissions of NOx and particulates are very low. - Energy efficiency is high. It is comparable to diesel engines. - Many different fuels (one at a time) can be used in the HCCI concept. There are also some hurdles to overcome: - Controlling combustion is difficult, it complicates engine design

  7. Bioethanol E85 as a fuel for dual fuel diesel engine

    International Nuclear Information System (INIS)

    Tutak, Wojciech

    2014-01-01

    Highlights: • An increase in the E85 fraction is changing the nature of the HRR course. • Change of combustion phasing with E85 fraction. • The ignition delay of dual fuel engine decreases with increasing E85 fuel. • Premixed combustion of E85 fuel reduces smoke emissions. - Abstract: This study investigates the potential of E85 fuelling in a diesel engine. Researches were performed using a three-cylinder a direct injection diesel engine. A dual-fuelling technology is implemented such that E85 is introduced into the intake manifold using a port-fuel injector while diesel is injected directly into the cylinder. The primary aim of the study was to determine the operating parameters of the engine powered on E85 bioethanol fuel in dual fuel system. The parameters that were taken into account are: engine efficiency, indicated mean effective pressure, heat release rate, combustion duration and ignition delay, combustion phasing and exhaust toxicity. With E85 fuel participation, NO x and soot emissions were reduced, whereas CO and HC emissions increased considerably. It was found that E85 participation in a combustible mixture reduced the excess air factor for the engine and this led to increased emissions of CO and HC, but decreased emissions of nitrogen oxides and soot

  8. Fuel octane effects in the partially premixed combustion regime in compression ignition engines

    NARCIS (Netherlands)

    Hildingsson, L.; Kalghatgi, G.T.; Tait, N.; Johansson, B.H.; Harrison, A.

    2009-01-01

    Previous work has showed that it may be advantageous to use fuels of lower cetane numbers compared to today's diesel fuels in compression ignition engines. The benefits come from the longer ignition delays that these fuels have. There is more time available for the fuel and air to mix before

  9. Theoretical study of the effects of pilot fuel quantity and its injection timing on the performance and emissions of a dual fuel diesel engine

    International Nuclear Information System (INIS)

    Papagiannakis, R.G.; Hountalas, D.T.; Rakopoulos, C.D.

    2007-01-01

    Various solutions have been proposed for improving the combustion process of conventional diesel engines and reducing the exhaust emissions without making serious modifications on the engine, one of which is the use of natural gas as a supplement for the conventional diesel fuel, the so called dual fuel natural gas diesel engines. The most common type of these is referred to as the pilot ignited natural gas diesel engine (PINGDE). Here, the primary fuel is natural gas that controls the engine power output, while the pilot diesel fuel injected near the end of the compression stroke auto-ignites and creates ignition sources for the surrounding gaseous fuel mixture to be burned. Previous research studies have shown that the main disadvantage of this dual fuel combustion is its negative impact on engine efficiency compared to the normal diesel operation, while carbon monoxide emissions are also increased. The pilot diesel fuel quantity and injection advance influence significantly the combustion mechanism. Then, in order to examine the effect of these two parameters on the performance and emissions, a comprehensive two-zone phenomenological model is employed and applied on a high-speed, pilot ignited, natural gas diesel engine located at the authors' laboratory. According to the results, the simultaneously increase of the pilot fuel quantity accompanied with an increase of its injection timing results to an improvement of the engine efficiency (increase) and of the emitted CO emissions (decrease) while it has a negative effect (increase) of NO emissions

  10. PERFORMANCE, EMISSION, AND COMBUSTION CHARACTERISTICS OF A CI ENGINE USING LIQUID PETROLEUM GAS AND NEEM OIL IN DUAL FUEL MODE

    Directory of Open Access Journals (Sweden)

    Palanimuthu Vijayabalan

    2010-01-01

    Full Text Available Increased environmental awareness and depletion of resources are driving the industries to develop viable alternative fuels like vegetable oils, compresed natural gas, liquid petroleum gas, producer gas, and biogas in order to provide suitable substitute to diesel for compression ignition engine. In this investigation, a single cylinder, vertical, air-cooled diesel engine was modified to use liquid petroleum gas in dual fuel mode. The liquefied petroleum gas, was mixed with air and supplied through intake manifold. The liquid fuel neem oil or diesel was injected into the combustion chamber. The performance, emission, and combustion characteristics were studied and compared for neat fuel and dual fuel mode. The experimental results on dual fuel engine show a reduction in oxides of nitrogen up to 70% of the rated power and smoke in the entire power range. However the brake thermal efficiency was found decreased in low power range due to lower calorific value of liquid petroleum gas, and increase in higher power range due to the complete burning of liquid petroleum gas. Hydrocarbon and carbon monoxide emissions were increased significantly at lower power range and marginal variation in higher power range.

  11. Fracture Failure Analysis of Fuel Pump Transmission Shaft of Dual-Fuel Engine

    Directory of Open Access Journals (Sweden)

    Chen Pei-hong

    2017-01-01

    Full Text Available NTS6ZLCz-129 dual-fuel turbocharged and intercooled engine durability test at 1000h, fuel pump shaft fractured. Fracture analysis, chemical analysis, microstructure examination and finite element stress analysis were carried out on the fractured shaft. The analysis result showed that the shaft fracture cause is forging fold. By improving the forging process, the forging fold was solved, and the durability test can be carried out smoothly.

  12. Achieving clean and efficient engine operation up to full load by combining optimized RCCI and dual-fuel diesel-gasoline combustion strategies

    International Nuclear Information System (INIS)

    Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Boronat, Vicente

    2017-01-01

    Highlights: • Optimized dual-fuel strategy to cover the whole engine load-speed map. • EURO VI NOx levels up to 14 bar IMEP with fully and highly premixed RCCI strategies. • Dual-fuel provides up to 7% higher efficiency than CDC if urea consumption is considered. - Abstract: This experimental work investigates the capabilities of the reactivity controlled compression ignition combustion concept to be operated in the whole engine map and discusses its benefits when compared to conventional diesel combustion. The experiments were conducted using a single-cylinder medium-duty diesel engine fueled with regular gasoline and diesel fuels. The main modification on the stock engine architecture was the addition of a port fuel injector in the intake manifold. In addition, with the aim of extending the reactivity controlled compression ignition operating range towards higher loads, the piston bowl volume was increased to reduce the compression ratio of the engine from 17.5:1 (stock) down to 15.3:1. To allow the dual-fuel operation over the whole engine map without exceeding the mechanical limitations of the engine, an optimized dual-fuel combustion strategy is proposed in this research. The combustion strategy changes as the engine load increases, starting from a fully premixed reactivity controlled compression ignition combustion up to around 8 bar IMEP, then switching to a highly premixed reactivity controlled compression ignition combustion up to 15 bar IMEP, and finally moving to a mainly diffusive dual-fuel combustion to reach the full load operation. The engine mapping results obtained using this combustion strategy show that reactivity controlled compression ignition combustion allows fulfilling the EURO VI NOx limit up to 14 bar IMEP. Ultra-low soot emissions are also achieved when the fully premixed combustion is promoted, however, the soot levels rise notably as the combustion strategy moves to a less premixed pattern. Finally, the direct comparison of

  13. Linear chemically sensitive electron tomography using DualEELS and dictionary-based compressed sensing

    Energy Technology Data Exchange (ETDEWEB)

    AlAfeef, Ala, E-mail: a.al-afeef.1@research.gla.ac.uk [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); School of Computing Science, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Bobynko, Joanna [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Cockshott, W. Paul. [School of Computing Science, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Craven, Alan J. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Zuazo, Ian; Barges, Patrick [ArcelorMittal Maizières Research, Maizières-lès-Metz 57283 (France); MacLaren, Ian, E-mail: ian.maclaren@glasgow.ac.uk [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

    2016-11-15

    We have investigated the use of DualEELS in elementally sensitive tilt series tomography in the scanning transmission electron microscope. A procedure is implemented using deconvolution to remove the effects of multiple scattering, followed by normalisation by the zero loss peak intensity. This is performed to produce a signal that is linearly dependent on the projected density of the element in each pixel. This method is compared with one that does not include deconvolution (although normalisation by the zero loss peak intensity is still performed). Additionally, we compare the 3D reconstruction using a new compressed sensing algorithm, DLET, with the well-established SIRT algorithm. VC precipitates, which are extracted from a steel on a carbon replica, are used in this study. It is found that the use of this linear signal results in a very even density throughout the precipitates. However, when deconvolution is omitted, a slight density reduction is observed in the cores of the precipitates (a so-called cupping artefact). Additionally, it is clearly demonstrated that the 3D morphology is much better reproduced using the DLET algorithm, with very little elongation in the missing wedge direction. It is therefore concluded that reliable elementally sensitive tilt tomography using EELS requires the appropriate use of DualEELS together with a suitable reconstruction algorithm, such as the compressed sensing based reconstruction algorithm used here, to make the best use of the limited data volume and signal to noise inherent in core-loss EELS. - Highlights: • DualEELS is essential for chemically sensitive electron tomography using EELS. • A new compressed sensing based algorithm (DLET) gives high fidelity reconstruction. • This combination of DualEELS and DLET will give reliable results from few projections.

  14. Econometric comparisons of liquid rocket engines for dual-fuel advanced earth-to-orbit shuttles

    Science.gov (United States)

    Martin, J. A.

    1978-01-01

    Econometric analyses of advanced Earth-to-orbit vehicles indicate that there are economic benefits from development of new vehicles beyond the space shuttle as traffic increases. Vehicle studies indicate the advantage of the dual-fuel propulsion in single-stage vehicles. This paper shows the economic effect of incorporating dual-fuel propulsion in advanced vehicles. Several dual-fuel propulsion systems are compared to a baseline hydrogen and oxygen system.

  15. Numerical Simulation of Methane Slip in Dual Fuel Marine Engines

    OpenAIRE

    Han, Jaehyun; Jensen, Michael Vincent; Pang, Kar Mun; Walther, Jens Honore; Schramm, Jesper; Bae, Choongsik

    2017-01-01

    The methane slip is the problematic issue for the engines using natural gas(NG). Because methane is more powerful greenhouse gas (GHG) than CO2, understanding of the methane slip during gas exchange process of the engines is essential. In this study, the influence of the gas pipe geometry and the valve timings on the methane slip was investigated. MAN L28/32DF engine was modeled to simulate the gas exchange process of the four stroke NG-diesel dual fuel engines. The mesh size of the model was...

  16. Prospects of biogas as dual fuel in small diesel engines

    International Nuclear Information System (INIS)

    Singh, Irvinder; Mittal, V.K.

    1992-01-01

    A study was conducted on diesel engines to find out the effect of induction rate of biogas on engine performance indices. The results of dual fuel engine performance was compared with diesel mode for various levels of biogas induction rate (0.3 to 7.2 l/s) engine load (20% to full load) and injection timing (20.6 to 48 before top dead centre). At full and 80% brake load, the best energy mix between diesel and biogas was 1.5:1 and 4:1 respectively. (author). 7 refs., 7 figs., 4 tabs

  17. Natural-gas fueled spark-ignition (SI) and compression-ignition (CI) engine performance and emissions

    Energy Technology Data Exchange (ETDEWEB)

    Korakianitis, T.; Namasivayam, A.M.; Crookes, R.J. [School of Engineering and Materials Science, Queen Mary University of London (United Kingdom)

    2011-02-15

    Natural gas is a fossil fuel that has been used and investigated extensively for use in spark-ignition (SI) and compression-ignition (CI) engines. Compared with conventional gasoline engines, SI engines using natural gas can run at higher compression ratios, thus producing higher thermal efficiencies but also increased nitrogen oxide (NO{sub x}) emissions, while producing lower emissions of carbon dioxide (CO{sub 2}), unburned hydrocarbons (HC) and carbon monoxide (CO). These engines also produce relatively less power than gasoline-fueled engines because of the convergence of one or more of three factors: a reduction in volumetric efficiency due to natural-gas injection in the intake manifold; the lower stoichiometric fuel/air ratio of natural gas compared to gasoline; and the lower equivalence ratio at which these engines may be run in order to reduce NO{sub x} emissions. High NO{sub x} emissions, especially at high loads, reduce with exhaust gas recirculation (EGR). However, EGR rates above a maximum value result in misfire and erratic engine operation. Hydrogen gas addition increases this EGR threshold significantly. In addition, hydrogen increases the flame speed of the natural gas-hydrogen mixture. Power levels can be increased with supercharging or turbocharging and intercooling. Natural gas is used to power CI engines via the dual-fuel mode, where a high-cetane fuel is injected along with the natural gas in order to provide a source of ignition for the charge. Thermal efficiency levels compared with normal diesel-fueled CI-engine operation are generally maintained with dual-fuel operation, and smoke levels are reduced significantly. At the same time, lower NO{sub x} and CO{sub 2} emissions, as well as higher HC and CO emissions compared with normal CI-engine operation at low and intermediate loads are recorded. These trends are caused by the low charge temperature and increased ignition delay, resulting in low combustion temperatures. Another factor is

  18. Performance and Exhaust Emissions in a Natural-Gas Fueled Dual-Fuel Engine

    Science.gov (United States)

    Shioji, Masahiro; Ishiyama, Takuji; Ikegami, Makoto; Mitani, Shinichi; Shibata, Hiroaki

    In order to establish the optimum fueling in a natural gas fueled dual fuel engine, experiments were done for some operational parameters on the engine performances and the exhaust emissions. The results show that the pilot fuel quantity should be increased and its injection timing should be advanced to suppress unburned hydrocarbon emission in the middle and low output range, while the quantity should be reduced and the timing retarded to avoid onset of knock at high loads. Unburned hydrocarbon emission and thermal efficiency are improved by avoiding too lean natural gas mixture by restricting intake charge air. However, the improvement is limited because the ignition of pilot fuel deteriorates with excessive throttling. It is concluded that an adequate combination of throttle control and equivalence ratio ensures low hydrocarbon emission and the thermal efficiency comparable to diesel operation.

  19. Design and Performance of LPG Fuel Mixer for Dual Fuel Diesel Engine

    Science.gov (United States)

    Desrial; Saputro, W.; Garcia, P. P.

    2018-05-01

    Small horizontal diesel engines are commonly used for agricultural machinery, however, availability of diesel fuel become one of big problems especially in remote area. Conversely, in line with government policy for conversion of kerosene into LPG for cooking, then LPG become more popular and available even in remote area. Therefore, LPG is potential fuel to replace the shortage of diesel fuel for operating diesel engine in remote area. The purpose of this study was to design mixing device for using dual fuel i.e. LPG and diesel fuel and evaluate its performance accordingly. Simulation by using CFD was done in order to analyze mixture characteristics of LPG in air intake manifold. The performance test was done by varying the amount of LPG injected in intake air at 20%, 25%, 30%, 35%, until 40%, respectively. Result of CFD contour simulation showed the best combination when mixing 30% LPG into the intake air. Performance test of this research revealed that mixing LPG in air intake can reduce the diesel fuel consumption about 0.7 l/hour (without load) and 1.14 l/hour (with load). Diesel engine revolution increases almost 300 rpm faster than when using diesel fuel only. Based on economic analysis, using the fuel combination (diesel fuel – LPG) is not recommended in the area near SPBU where the price of diesel fuel is standard. However, using the fuel combination LPG-diesel fuel is highly recommended in the remote areas in Indonesia where price of diesel fuel is comparatively expensive which will provide cheaper total fuel cost for diesel engine operation.

  20. Removal of methane from compressed natural gas fueled vehicle exhaust

    International Nuclear Information System (INIS)

    Subramanian, S.; Kudla, R.J.; Chattha, M.S.

    1992-01-01

    The objective of this paper is to investigate the modes of methane (CH 4 ) removal from simulated compressed natural gas (CNG) fueled vehicle exhaust under net oxidizing, net reducing, and stoichiometric conditions. Model reaction studies were conducted. The results suggest that the oxidation of methane with oxygen contributes to the removal of methane under net oxidizing conditions. In contrast, the oxidation of methane with oxygen as well as nitric oxide contributes to its removal under net reducing conditions. The steam reforming reaction does not significantly contribute to the removal of methane. The methane conversions under net reducing conditions are higher than those observed under net oxidizing conditions. The study shows that the presence of carbon monoxide in the feed gas leads to a gradual decrease in the methane conversion with increasing redox ratio, under net oxidizing conditions. a minimum in methane conversion is observed at a redox ratio of 0. 8. The higher activity for the methane-oxygen reaction resulting from a lowering in the overall oxidation state of palladium and the contribution of the methane-nitric oxide reaction toward the removal of CH 4 appear to account for the higher CH 4 conversions observed under net reducing conditions

  1. Measurement of Quasi-periodic Oscillating Flow Motion in Simulated Dual-cooled Annular Fuel Bundle

    International Nuclear Information System (INIS)

    Lee, Chi Young; Shin, Chang Hwan; Park, Ju Yong; Oh, Dong Seok; Chun, Tae Hyun; In, Wang Kee

    2012-01-01

    In order to increase a significant amount of reactor power in OPR1000, KAERI (Korea Atomic Energy Research Institute) has been developing a dual-cooled annular fuel. The dual-cooled annular fuel is simultaneously cooled by the water flow through the inner and the outer channels. KAERI proposed the 12x12 dual-cooled annular fuel array which was designed to be structurally compatible with the 16x16 cylindrical solid fuel array by maintaining the same array size and the guide tubes in the same locations, as shown in Fig. 1. In such a case, due to larger outer diameter of dual-cooled annular fuel than conventional solid fuel, a P/D (Pitch-to-Diameter ratio) of dual cooled annular fuel assembly becomes smaller than that of cylindrical solid fuel. A change in P/D of fuel bundle can cause a difference in the flow mixing phenomena between the dual-cooled annular and conventional cylindrical solid fuel assemblies. In this study, the rod bundle flow motion appearing in a small P/D case is investigated preliminarily using PIV (Particle Image Velocimetry) for dual-cooled annular fuel application

  2. Effect of the Ethanol Injection Moment During Compression Stroke on the Combustion of Ethanol - Diesel Dual Direct Injection Engine

    Science.gov (United States)

    Liang, Yu; Zhou, Liying; Huang, Haomin; Xu, Mingfei; Guo, Mei; Chen, Xin

    2018-01-01

    A set of GDI system is installed on a F188 single-cylinder, air-cooled and direct injection diesel engine, which is used for ethanol injection, with the injection time controlled by the crank angle signal collected by AVL angle encoder. The injection of ethanol amounts to half of the thermal equivalent of an original diesel fuel. A 3D combustion model is established for the ethanol - diesel dual direct injection engine. Diesel was injected from the original fuel injection system, with a fuel supply advance angle of 20°CA. The ethanol was injected into the cylinder during compression process. Diesel injection began after the completion of ethanol injection. Ethanol injection starting point of 240°CA, 260°CA, 280°CA, 300°CA and 319.4°CA were simulated and analyzed. Due to the different timing of ethanol injection, the ignition of the ethanol mixture when diesel fires, results in non-uniform ignition distribution and flame propagation rate, since the distribution and concentration gradients of the ethanol mixture in the cylinder are different, thus affecting the combustion process. The results show that, when ethanol is injected at 319.4°CA, the combustion heat release rate and the pressure rise rate during the initial stage are the highest. Also, the maximum combustion pressure, with a relatively advance phase, is the highest. In case of later initial ethanol injection, the average temperature in the cylinder during the initial combustion period will have a faster rise. In case of initial injection at 319.4°CA, the average temperature in the cylinder is the highest, followed by 240°CA ethanol injection. In the post-combustion stage, the earlier ethanol injection will result in higher average temperature in the cylinder and more complete fuel combustion. The injection of ethanol at 319.4°CA produces earlier and highest NOX emissions.

  3. Performance Study of Dual Fuel Engine Using Producer Gas as Secondary Fuel

    Directory of Open Access Journals (Sweden)

    Deepika Shaw

    2016-06-01

    Full Text Available In the present paper, development of producer gas fuelled 4 stroke diesel engine has been investigated. Producer gas from biomass has been examined and successfully operated with 4 stroke diesel engine. The effects of higher and lower loads were investigated on the dual fuel mode. The experimental investigations revealed that at lower loads dual fuel operation with producer gas shows lower efficiency due to lower combustion rate cause by low calorific value of the producer gas. Beyond 40% load the brake thermal efficiency of dual fuel operation improved due to faster combustion rate of producer gas and higher level of premixing. It can be observed that at lower load and 20% opening of producer gas the gaseous fuel substitution found to be 56% whereas at 100% opening of producer gas it reaches 78% substitution. The CO2 emission increased at high producer gas opening and high load because at 100% producer gas maximum atoms of carbons were there and at high load condition the diesel use increased. At 80% load and producer gas varying from 20% to 100. Power output was almost comparable to diesel power with marginal higher efficiency. Producer gas is one such technology which is environmentally benign and holds large promise for future.

  4. Effect of variation in LPG composition on emissions and performance in a dual fuel diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    H.E. Saleh [Mattaria, Helwan University, Cairo (Egypt). Department of Mechanical Power Engineering

    2008-10-15

    This paper investigates the effect of variation in LPG composition on emissions and performance characteristics in a dual fuel engine run on diesel fuel and five gaseous fuel of LPG with different composition. To quantify the best LPG composition for dual fuel operation especially in order to improve the exhaust emissions quality while maintaining high thermal efficiency comparable to a conventional diesel engine, a two-cylinder, naturally aspirated, four-stroke, DI diesel engine converted to run as pilot-injected dual fuel engine. The tests and data collection were performed under various conditions of load at constant engine speed. From the results, it is observed that the exhaust emissions and fuel conversion efficiency of the dual fuel engine are found to be affected when different LPG composition is used as higher butane content lead to lower NOx levels while higher propane content reduces CO levels. Fuel No. 3 (70% propane, 30% butane) with mass fraction 40% substitution of the diesel fuel was the best LPG composition in the dual fuel operation except that at part loads. Also, tests were made for fuel No. 3-diesel blend in the dual fuel operation at part loads to improve the engine performances and exhaust emissions by using the Exhaust Gas Recirculation (EGR) method. 26 refs., 15 figs., 5 tabs.

  5. Dual photon excitation microscopy and image threshold segmentation in live cell imaging during compression testing.

    Science.gov (United States)

    Moo, Eng Kuan; Abusara, Ziad; Abu Osman, Noor Azuan; Pingguan-Murphy, Belinda; Herzog, Walter

    2013-08-09

    Morphological studies of live connective tissue cells are imperative to helping understand cellular responses to mechanical stimuli. However, photobleaching is a constant problem to accurate and reliable live cell fluorescent imaging, and various image thresholding methods have been adopted to account for photobleaching effects. Previous studies showed that dual photon excitation (DPE) techniques are superior over conventional one photon excitation (OPE) confocal techniques in minimizing photobleaching. In this study, we investigated the effects of photobleaching resulting from OPE and DPE on morphology of in situ articular cartilage chondrocytes across repeat laser exposures. Additionally, we compared the effectiveness of three commonly-used image thresholding methods in accounting for photobleaching effects, with and without tissue loading through compression. In general, photobleaching leads to an apparent volume reduction for subsequent image scans. Performing seven consecutive scans of chondrocytes in unloaded cartilage, we found that the apparent cell volume loss caused by DPE microscopy is much smaller than that observed using OPE microscopy. Applying scan-specific image thresholds did not prevent the photobleaching-induced volume loss, and volume reductions were non-uniform over the seven repeat scans. During cartilage loading through compression, cell fluorescence increased and, depending on the thresholding method used, led to different volume changes. Therefore, different conclusions on cell volume changes may be drawn during tissue compression, depending on the image thresholding methods used. In conclusion, our findings confirm that photobleaching directly affects cell morphology measurements, and that DPE causes less photobleaching artifacts than OPE for uncompressed cells. When cells are compressed during tissue loading, a complicated interplay between photobleaching effects and compression-induced fluorescence increase may lead to interpretations in

  6. Numerical modeling on homogeneous charge compression ignition combustion engine fueled by diesel-ethanol blends

    OpenAIRE

    Hanafi H.; Hasan M.M; Rahman M.M; Noor M.M; Kadirgama K.; Ramasamy D.

    2016-01-01

    This paper investigates the performance and emission characteristics of HCCI engines fueled with oxygenated fuels (ethanol blend). A modeling study was conducted to investigate the impact of ethanol addition on the performance, combustion and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI) engine fueled by diesel. One dimensional simulation was conducted using the renowned commercial software for diesel and its blend fuels with 5% (E5) and 10% ethanol (E10) (in vo...

  7. An investigation on the particulate number and size distributions over the whole engine map from an optimized combustion strategy combining RCCI and dual-fuel diesel-gasoline

    International Nuclear Information System (INIS)

    Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Boronat, Vicente

    2017-01-01

    Highlights: • Optimized dual-mode dual-fuel strategy to cover the whole engine map. • High coherence between smoke and total particles number for diffusive dual-fuel mode. • Fully premixed RCCI regime dominated by small particles of 30 nm diameter peak. • Highly premixed RCCI mode has a transitional behavior with two particle diameter peaks. - Abstract: Literature demonstrates that, for premixed low temperature combustion concepts, particulate matter cannot be directly extrapolated from soot emissions measurements, as typically done for conventional diesel combustion. This is because the particulate matter from low temperature combustion has low fraction of carbonaceous compounds and great amount of soluble organic fraction, which is not captured by the smoke measurement techniques such as the optical reflectometry. By this reason, the study of the particulate matter characteristics from this combustion techniques requires using specific equipment. The aim of the current work is to gain understanding on the particulate matter characteristics from the dual-mode dual-fuel combustion, which is an optimized combustion strategy that combines fully and highly premixed RCCI regimes at low and medium loads, and switches to dual-fuel diffusion combustion at full load. The study was performed over the whole engine map, using a 15.3:1 compression ratio medium-duty EURO VI diesel engine. In particular, the particulate number and size distributions were sampled using a scanning mobility particle sizer and a condensation particle counter, which allow measuring the size distribution and total number of particles from 5 to 250 nm. Results demonstrate that the fully premixed RCCI combustion is dominated by small particles (less than 30 nm in mobility diameter), the dual-fuel diffusion mode is dominated by larger particles (around 100 nm in mobility diameter) showing more diesel-like particle size distributions, and the highly premixed reactivity controlled compression

  8. Dual fuel mode operation in diesel engines using renewable fuels: Rubber seed oil and coir-pith producer gas

    Energy Technology Data Exchange (ETDEWEB)

    Ramadhas, A.S.; Jayaraj, S.; Muraleedharan, C. [Department of Mechanical Engineering, National Institute of Technology Calicut, Calicut-673601 (India)

    2008-09-15

    Partial combustion of biomass in the gasifier generates producer gas that can be used as supplementary or sole fuel for internal combustion engines. Dual fuel mode operation using coir-pith derived producer gas and rubber seed oil as pilot fuel was analyzed for various producer gas-air flow ratios and at different load conditions. The engine is experimentally optimized with respect to maximum pilot fuel savings in the dual fuel mode operation. The performance and emission characteristics of the dual fuel engine are compared with that of diesel engine at different load conditions. Specific energy consumption in the dual-fuel mode of operation with oil-coir-pith operation is found to be in the higher side at all load conditions. Exhaust emission was found to be higher in the case of dual fuel mode of operation as compared to neat diesel/oil operation. Engine performance characteristics are inferior in fully renewable fueled engine operation but it suitable for stationary engine application, particularly power generation. (author)

  9. Improving the performance and fuel consumption of dual chamber stratified charge spark ignition engines

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, S.C.; Pan, S.S.; Bruckbauer, J.J.; Gehrke, G.R.

    1979-09-01

    A combined experimental and theoretical investigation of the nature of the combustion processes in a dual chamber stratified charge spark ignition engine is described. This work concentrated on understanding the mixing process in the main chamber gases. A specially constructed single cylinder engine was used to both conduct experiments to study mixing effects and to obtain experimental data for the validation of the computer model which was constructed in the theoretical portion of the study. The test procedures are described. Studies were conducted on the effect of fuel injection timing on performance and emissions using the combination of orifice size and prechamber to main chamber flow rate ratio which gave the best overall compromise between emissions and performance. In general, fuel injection gave slightly higher oxides of nitrogen, but considerably lower hydrocarbon and carbon monoxide emissions than the carbureted form of the engine. Experiments with engine intake port redesign to promote swirl mixing indicated a substantial increase in the power output from the engine and, that an equivalent power levels, the nitric oxide emissions are approximately 30% lower with swirl in the main chamber than without swirl. The development of a computer simulation of the combustion process showed that a one-dimensional combustion model can be used to accurately predict trends in engine operation conditions and nitric oxide emissions even though the actual flame in the engine is not completely one-dimensional, and that a simple model for mixing of the main chamber and prechamber intake gases at the start of compression proved adequate to explain the effects of swirl, ignition timing, overall fuel air ratio, volumetric efficiency, and variations in prechamber air fuel ratio and fuel rate percentage on engine power and nitric oxide emissions. (LCL)

  10. Effect of biodiesel blends on engine performance and exhaust emission for diesel dual fuel engine

    International Nuclear Information System (INIS)

    Mohsin, R.; Majid, Z.A.; Shihnan, A.H.; Nasri, N.S.; Sharer, Z.

    2014-01-01

    Highlights: • Engine and emission characteristics of biodiesel DDF engine system were measured. • Biodiesel DDF fuelled system produced high engine performance. • Lower hydrocarbons and carbon dioxide was emitted by biodiesel DDF system. • Biodiesel DDF produced slightly higher carbon monoxide and nitric oxides emission. - Abstract: Biodiesel derived from biomass is a renewable source of fuel. It is renovated to be the possible fuel to replace fossil derived diesel due to its properties and combustion characteristics. The integration of compressed natural gas (CNG) in diesel engine known as diesel dual fuel (DDF) system offered better exhaust emission thus become an attractive option for reducing the pollutants emitted from transportation fleets. In the present study, the engine performance and exhaust emission of HINO H07C DDF engine; fuelled by diesel, biodiesel, diesel–CNG, and biodiesel–CNG, were experimentally studied. Biodiesel and diesel fuelled engine system respectively generated 455 N m and 287 N m of torque. The horse power of biodiesel was found to be 10–20% higher compared to diesel. Biodiesel–CNG at 20% (B20-DDF) produced the highest engine torque compared to other fuel blends Biodiesel significantly increase the carbon monoxide (15–32%) and nitric oxides (6.67–7.03%) but in contrast reduce the unburned hydrocarbons (5.76–6.25%) and carbon dioxide (0.47–0.58%) emissions level. These results indicated that biodiesel could be used without any engine modifications as an alternative and environmentally friendly fuel especially the heavy transportation fleets

  11. Influence of performance characteristic of a gaseous fuel supply system on hydrocarbon emissions of a dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Ren, J.; Wang, Z.Y.; Zhong, H.; Hao, S.H. [Xi' an Jiaotong Univ., Dept. of Automobile Engineering, Xi' an (China)

    2000-11-01

    The performance of the gaseous fuel supply and its influence on hydrocarbon (HC) emissions of dual-fuel engines have been investigated. A new design of manifold respirators with mixers is also presented in the paper. The design of the gaseous fuel supply system has a great influence on HC emissions in the dual-fuel engine at light load. The problem of scavenging is discussed and solved by using the manifold respirators in the dual-fuel engine. It performs the function of retarding the gaseous fuel entry timing from the moment of intake valve opening, and its delaying effects have been measured and tested. Experimental results show that the manifold respirator gives the best performance in reducing HC emissions compared with a common pipe mixer and a respirator with bo miser. In addition, the mixing effects are sensitive to the mixer configuration. (Author)

  12. Improvement performance and emissions in a diesel engine dual-fueled with natural gas; Tennen gas dual fuel diesel kikan no seino haishutsu gas tokusei no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, S; Okamoto, T; Kusaka, J; Daisho, Y; Kihara, R; Saito, T [Waseda University, Tokyo (Japan)

    1997-10-01

    This paper deals with a study on combustion and emission characteristics of a direct injection diesel engine dual-fueled with natural gas. Dual fueling systems tend to emit high unburned fuel especially at low load, resulting in a decreased thermal efficiency. This is because natural gas-air mixtures are too lean for flame to propagate under low load conditions. Intake charge heating and uncooled EGR are very useful to improve emissions and thermal efficiency at low load. Such favorable effects are supported by NO kinetic simulations. 2 refs., 13 figs.

  13. Impact of thermodynamic properties and heat loss on ignition of transportation fuels in rapid compression machines

    KAUST Repository

    Ahmed, Ahfaz

    2018-01-30

    Rapid compression machines (RCM) are extensively used to study autoignition of a wide variety of fuels at engine relevant conditions. Fuels ranging from pure species to full boiling range gasoline and diesel can be studied in an RCM to develop a better understanding of autoignition kinetics in low to intermediate temperature ranges. In an RCM, autoignition is achieved by compressing a fuel/oxidizer mixture to higher pressure and temperature, thereby initiating chemical reactions promoting ignition. During these experiments, the pressure is continuously monitored and is used to deduce significant events such as the end of compression and the onset of ignition. The pressure profile is also used to assess the temperature evolution of the gas mixture with time using the adiabatic core hypothesis and the heat capacity ratio of the gas mixture. In such RCM studies, real transportation fuels containing many components are often represented by simpler surrogate fuels. While simpler surrogates such as primary reference fuels (PRFs) and ternary primary reference fuel (TPRFs) can match research and motor octane number of transportation fuels, they may not accurately replicate thermodynamic properties (including heat capacity ratio). This non-conformity could exhibit significant discrepancies in the end of compression temperature, thereby affecting ignition delay (τign) measurements. Another aspect of RCMs that can affect τign measurement is post compression heat loss, which depends on various RCM parameters including geometry, extent of insulation, pre-heating temperature etc. To, better understand the effects of these non-chemical kinetic parameters on τign, thermodynamic properties of a number of FACE G gasoline surrogates were calculated and simulated in a multi-zone RCM model. The problem was further investigated using a variance based analysis and individual sensitivities were calculated. This study highlights the effects on τign due to thermodynamic properties of

  14. Impact of thermodynamic properties and heat loss on ignition of transportation fuels in rapid compression machines

    KAUST Repository

    Ahmed, Ahfaz; Hantouche, Mireille; Khurshid, Muneeb; Mohamed, Samah; Nasir, Ehson Fawad; Farooq, Aamir; Roberts, William L.; Knio, Omar; Sarathy, Mani

    2018-01-01

    Rapid compression machines (RCM) are extensively used to study autoignition of a wide variety of fuels at engine relevant conditions. Fuels ranging from pure species to full boiling range gasoline and diesel can be studied in an RCM to develop a better understanding of autoignition kinetics in low to intermediate temperature ranges. In an RCM, autoignition is achieved by compressing a fuel/oxidizer mixture to higher pressure and temperature, thereby initiating chemical reactions promoting ignition. During these experiments, the pressure is continuously monitored and is used to deduce significant events such as the end of compression and the onset of ignition. The pressure profile is also used to assess the temperature evolution of the gas mixture with time using the adiabatic core hypothesis and the heat capacity ratio of the gas mixture. In such RCM studies, real transportation fuels containing many components are often represented by simpler surrogate fuels. While simpler surrogates such as primary reference fuels (PRFs) and ternary primary reference fuel (TPRFs) can match research and motor octane number of transportation fuels, they may not accurately replicate thermodynamic properties (including heat capacity ratio). This non-conformity could exhibit significant discrepancies in the end of compression temperature, thereby affecting ignition delay (τign) measurements. Another aspect of RCMs that can affect τign measurement is post compression heat loss, which depends on various RCM parameters including geometry, extent of insulation, pre-heating temperature etc. To, better understand the effects of these non-chemical kinetic parameters on τign, thermodynamic properties of a number of FACE G gasoline surrogates were calculated and simulated in a multi-zone RCM model. The problem was further investigated using a variance based analysis and individual sensitivities were calculated. This study highlights the effects on τign due to thermodynamic properties of

  15. Experimental investigations of effects of EGR on performance and emissions characteristics of CNG fueled reactivity controlled compression ignition (RCCI) engine

    International Nuclear Information System (INIS)

    Singh Kalsi, Sunmeet; Subramanian, K.A.

    2016-01-01

    Highlights: • NO_x emission decreased drastically in RCCI engine with EGR. • CO and HC emissions decreased with 8% EGR. • Smoke emission increased with EGR but is still less than base diesel. • Brake thermal efficiency does not change with EGR up to 15% • 8% EGR is optimum based on less CO, HC, NO_x except smoke. - Abstract: Experimental: tests were carried out on a single cylinder diesel engine (7.4 kW rated power at 1500 rpm) under dual fuel mode (CNG-Diesel) with EGR (exhaust gas recirculation). Less reacting fuel (CNG) was injected inside the intake manifold using timed manifold gas injection system whereas high reactive diesel fuel was directly injected into the engine’s cylinder for initiation of ignition. EGR at different percentages (8%, 15% and 30%) was inducted to the engine through intake manifold and tests were conducted at alternator power output of 2 kW and 5 kW. The engine can operate under dual fuel mode with maximum CNG energy share of 85% and 92% at 5 kW and 2 kW respectively. The brake thermal efficiency of diesel engine improved marginally at 5 kW power output under conventional dual fuel mode with the CNG share up to 37% whereas the efficiency did not change with up to 15% EGR however it decreased beyond the EGR percentage. NO_x emission in diesel engine under conventional dual fuel mode decreased significantly and it further decreased drastically with EGR. The notable point emerged from this study is that CO and HC emissions, which are major problems at part load in reactivity controlled compression ignition engine (RCCI), decreased with 8% EGR along with further reduction of NO_x. However, smoke emission is marginally higher with EGR than without EGR but it is still less than conventional mode (Diesel alone). The new concept emerged from this study is that CO and HC emissions of RCCI engine at part load can be reduced using EGR.

  16. Combustion and Emission Characteristics of Variable Compression Ignition Engine Fueled with Jatropha curcas Ethyl Ester Blends at Different Compression Ratio

    Directory of Open Access Journals (Sweden)

    Rajneesh Kumar

    2014-01-01

    Full Text Available Engine performance and emission characteristics of unmodified biodiesel fueled diesel engines are highly influenced by their ignition and combustion behavior. In this study, emission and combustion characteristics were studied when the engine operated using the different blends (B10, B20, B30, and B40 and normal diesel fuel (B0 as well as when varying the compression ratio from 16.5 : 1 to 17.5 : 1 to 18.5 : 1. The change of compression ratio from 16.5 : 1 to 18.5 : 1 resulted in 27.1%, 27.29%, 26.38%, 28.48%, and 34.68% increase in cylinder pressure for the blends B0, B10, B20, B30, and B40, respectively, at 75% of rated load conditions. Higher peak heat release rate increased by 23.19%, 14.03%, 26.32%, 21.87%, and 25.53% for the blends B0, B10, B20, B30, and B40, respectively, at 75% of rated load conditions, when compression ratio was increased from16.5 : 1 to 18.5 : 1. The delay period decreased by 21.26%, CO emission reduced by 14.28%, and NOx emission increased by 22.84% for B40 blends at 75% of rated load conditions, when compression ratio was increased from 16.5 : 1 to 18.5 : 1. It is concluded that Jatropha oil ester can be used as fuel in diesel engine by blending it with diesel fuel.

  17. Performance and emission characteristics of turpentine-diesel dual fuel engine and knock suppression using water diluents

    Energy Technology Data Exchange (ETDEWEB)

    Karthikeyan, R. [Adhiparasakthi Engineering College, Tamil Nadu (India); Mahalakshmi, N.V. [College of Engineering Guindy, Tamil Nadu (India). Dept. of Mechanical Engineering

    2007-08-15

    In the present work, a normal diesel engine was modified to work in a dual fuel (DF) mode with turpentine and diesel as primary and pilot fuels, respectively. The resulting homogeneous mixture was compressed to a temperature below the self-ignition point. The pilot fuel was injected through the standard injection system and initiated the combustion in the primary-fuel air mixture. The primary fuel (turpentine) has supplied most of the heat energy. Usually, in all DF engines, low-cetane fuels are preferred as a primary fuel. Therefore, at higher loads these fuels start knocking and deteriorating in performances. Usually, DF operators suppress the knock by adding more pilot-fuel quantity. But in the present work, a minimum pilot-fuel quantity was maintained constant throughout the test and a required quantity of diluent (water) was added into the combustion at the time of knocking. The advantages of this method of knock suppression are restoration of performance at full load, maintenance of the same pilot quantity through the load range and reduction in the fuel consumption at full load. From the results, it was found that all performance and emission parameters of turpentine, except volumetric efficiency, are better than those of diesel fuel. The emissions like CO, UBHC are higher than those of the diesel baseline (DBL) and around 40-45% reduction of smoke was observed at 100% of full load. The major pollutant of diesel engine, NO{sub x}, was found to be equal to that of DBL. From the above experiment, it was proved that approximately 80% replacement of diesel with turpentine is quite possible. (author)

  18. Modeling of Single and Dual Reservoir Porous Media Compressed Gas (Air and CO2) Storage Systems

    Science.gov (United States)

    Oldenburg, C. M.; Liu, H.; Borgia, A.; Pan, L.

    2017-12-01

    Intermittent renewable energy sources are causing increasing demand for energy storage. The deep subsurface offers promising opportunities for energy storage because it can safely contain high-pressure gases. Porous media compressed air energy storage (PM-CAES) is one approach, although the only facilities in operation are in caverns (C-CAES) rather than porous media. Just like in C-CAES, PM-CAES operates generally by injecting working gas (air) through well(s) into the reservoir compressing the cushion gas (existing air in the reservoir). During energy recovery, high-pressure air from the reservoir is mixed with fuel in a combustion turbine to produce electricity, thereby reducing compression costs. Unlike in C-CAES, the storage of energy in PM-CAES occurs variably across pressure gradients in the formation, while the solid grains of the matrix can release/store heat. Because air is the working gas, PM-CAES has fairly low thermal efficiency and low energy storage density. To improve the energy storage density, we have conceived and modeled a closed-loop two-reservoir compressed CO2 energy storage system. One reservoir is the low-pressure reservoir, and the other is the high-pressure reservoir. CO2 is cycled back and forth between reservoirs depending on whether energy needs to be stored or recovered. We have carried out thermodynamic and parametric analyses of the performance of an idealized two-reservoir CO2 energy storage system under supercritical and transcritical conditions for CO2 using a steady-state model. Results show that the transcritical compressed CO2 energy storage system has higher round-trip efficiency and exergy efficiency, and larger energy storage density than the supercritical compressed CO2 energy storage. However, the configuration of supercritical compressed CO2 energy storage is simpler, and the energy storage densities of the two systems are both higher than that of PM-CAES, which is advantageous in terms of storage volume for a given

  19. Likelihood and consequences of fuel string compression at Point Lepreau Generating Station

    International Nuclear Information System (INIS)

    Reid, P.J.; Gibb, R.A.

    1996-01-01

    During an accident which results in fuel heatup, axial thermal expansion of the fuel string relative to the pressure tube will occur. If the temperature transient is sufficiently severe, the fuel string may contact the shieled plugs at both ends of the channel. Any additional axial thermal expansion will result in deformation of fuel and fuel channel components, leading to tensile or compressive stresses in the different fuel channel components. If these loads become sufficiently large, they could result in failure of a fuel channel component or to channel failure due to bending of a fuel element under load. The analysis described in this paper demonstrates that this process would not result in fuel channel failure for a design basis accident at Point Lepreau Generating Station (PLGS), even if the station were retubed to 'as-built' channel lengths. (author)

  20. Dual-fuel natural gas/diesel engines: Technology, performance, and emissions

    Science.gov (United States)

    Turner, S. H.; Weaver, C. S.

    1994-11-01

    An investigation of current dual-fuel natural gas/diesel engine design, performance, and emissions was conducted. The most pressing technological problems associated with dual-fuel engine use were identified along with potential solutions. It was concluded that dual-fuel engines can achieve low NO(sub x) and particulate emissions while retaining fuel-efficiency and BMEP levels comparable to those of diesel engines. The investigation also examined the potential economic impact of dual-fuel engines in diesel-electric locomotives, marine vessels, farm equipment, construction, mining, and industrial equipment, and stand-alone electricity generation systems. Recommendations for further additional funding to support research, development, and demonstration in these applications were then presented.

  1. Thermodynamic modeling of LPG combustion in dual-fuel engines; Modelisation thermodynamique de la combustion du GPL dans les moteurs dual-fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bilcan, A.; Le Corre, O.; Tazerout, M. [Ecole des Mines de Nantes, 44 (France); Ramesh, A. [Indian Institute of Technology Madras (India)

    2002-07-01

    Dual-fuel engines are modified diesel engines burning simultaneously two fuels inside the cylinder: a gaseous one, called the primary fuel and a liquid one, called the pilot fuel. The thermal efficiency of the dual-fuel engine and of the diesel engine are comparable; the level of emissions is lower compared to the diesel one. This article presents a new procedure for the combustion modeling in a LPG-diesel dual-fuel engine. The procedures deals with the ignition delay period and with the rate of heat release inside the cylinder. This procedure is validated using experimental data issued front a collaboration with the Indian Institute of Technology from Madras, India. The used engine is a single-cylinder one, air-cooled. The pilot fuel is direct injected inside the cylinder The engine was run at constant load and with different diesel substitutions, i.e. for different air to fuel ratios of the primary fuel-air mixture. The general error of the procedure is below 10%. (authors)

  2. Numerical Simulations of Hollow-Cone Injection and Gasoline Compression Ignition Combustion With Naphtha Fuels

    KAUST Repository

    Badra, Jihad A.

    2016-01-29

    Gasoline compression ignition (GCI), also known as partially premixed compression ignition (PPCI) and gasoline direct injection compression ignition (GDICI), engines have been considered an attractive alternative to traditional spark ignition (SI) engines. Lean-burn combustion with the direct injection of fuel eliminates throttle losses for higher thermodynamic efficiencies, and the precise control of the mixture compositions allows better emission performance such as NOx and particulate matter (PM). Recently, low octane gasoline fuel has been identified as a viable option for the GCI engine applications due to its longer ignition delay characteristics compared to diesel and lighter evaporation compared to gasoline fuel (Chang et al., 2012, "Enabling High Efficiency Direct Injection Engine With Naphtha Fuel Through Partially Premixed Charge Compression Ignition Combustion," SAE Technical Paper No. 2012-01-0677). The feasibility of such a concept has been demonstrated by experimental investigations at Saudi Aramco (Chang et al., 2012, "Enabling High Efficiency Direct Injection Engine With Naphtha Fuel Through Partially Premixed Charge Compression Ignition Combustion," SAE Technical Paper No. 2012-01-0677; Chang et al., 2013, "Fuel Economy Potential of Partially Premixed Compression Ignition (PPCI) Combustion With Naphtha Fuel," SAE Technical Paper No. 2013-01-2701). The present study aims to develop predictive capabilities for low octane gasoline fuel compression ignition (CI) engines with accurate characterization of the spray dynamics and combustion processes. Full three-dimensional simulations were conducted using converge as a basic modeling framework, using Reynolds-averaged Navier-Stokes (RANS) turbulent mixing models. An outwardly opening hollow-cone spray injector was characterized and validated against existing and new experimental data. An emphasis was made on the spray penetration characteristics. Various spray breakup and collision models have been

  3. Experimental Investigation Of Biogas-Biodiesel Dual Fuel Combustion In A Diesel Engine

    Directory of Open Access Journals (Sweden)

    Ramesha D. K.

    2015-06-01

    Full Text Available This study is an attempt at achieving diesel fuel equivalent performance from diesel engines with maximum substitution of diesel with renewable fuels. In this context the study has been designed to analyze the influence of B20 algae biodiesel as a pilot fuel in a biodiesel biogas dual fuel engine, and results are compared to those of biodiesel and diesel operation at identical engine settings. Experiments were performed at various loads from 0 to 100 % of maximum load at a constant speed of 1500 rpm. In general, B20 algae biodiesel is compatible with diesel in terms of performance and combustion characteristics. Dual fuel mode operation displays lower thermal efficiency and higher fuel consumption than for other fuel modes of the test run across the range of engine loads. Dual fuel mode displayed lower emissions of NOx and Smoke opacity while HC and CO concentrations were considerably higher as compared to other fuels. In dual fuel mode peak pressure and heat release rate were slightly higher compared to diesel and biodiesel mode of operation for all engine loads.

  4. THE EFFECT OF VARIABLE COMPRESSION RATIO ON FUEL CONSUMPTION IN SPARK IGNITION ENGINES

    Directory of Open Access Journals (Sweden)

    Yakup SEKMEN

    2002-02-01

    Full Text Available Due to lack of energy sources in the world, we are obliged to use our current energy sources in the most efficient way. Therefore, in the automotive industry, research works to manufacture more economic cars in terms of fuelconsumption and environmental friendly cars, at the same time satisfying the required performance have been intensively increasing. Some positive results have been obtained by the studies, aimed to change the compression ratio according to the operating conditions of engine. In spark ignition engines in order to improve the combustion efficiency, fuel economy and exhaust emission in the partial loads, the compression ratio must be increased; but, under the high load and low speed conditions to prevent probable knock and hard running compression ratio must be decreased slightly. In this paper, various research works on the variable compression ratio with spark ignition engines, the effects on fuel economy, power output and thermal efficiency have been investigated. According to the results of the experiments performed with engines having variable compression ratio under the partial and mid-load conditions, an increase in engine power, a decrease in fuel consumption, particularly in partial loads up to 30 percent of fuel economy, and also severe reductions of some exhaust emission values were determined.

  5. Numerical Simulations of Hollow Cone Injection and Gasoline Compression Ignition Combustion With Naphtha Fuels

    KAUST Repository

    Badra, Jihad A.

    2016-01-11

    Gasoline compression ignition (GCI), also known as partially premixed compression ignition (PPCI) and gasoline direct injection compression ignition (GDICI), engines have been considered an attractive alternative to traditional spark ignition engines. Lean burn combustion with the direct injection of fuel eliminates throttle losses for higher thermodynamic efficiencies, and the precise control of the mixture compositions allows better emission performance such as NOx and particulate matter (PM). Recently, low octane gasoline fuel has been identified as a viable option for the GCI engine applications due to its longer ignition delay characteristics compared to diesel and lighter evaporation compared to gasoline fuel [1]. The feasibility of such a concept has been demonstrated by experimental investigations at Saudi Aramco [1, 2]. The present study aims to develop predictive capabilities for low octane gasoline fuel compression ignition engines with accurate characterization of the spray dynamics and combustion processes. Full three-dimensional simulations were conducted using CONVERGE as a basic modeling framework, using Reynolds-averaged Navier-Stokes (RANS) turbulent mixing models. An outwardly opening hollow-cone spray injector was characterized and validated against existing and new experimental data. An emphasis was made on the spray penetration characteristics. Various spray breakup and collision models have been tested and compared with the experimental data. An optimum combination has been identified and applied in the combusting GCI simulations. Linear instability sheet atomization (LISA) breakup model and modified Kelvin-Helmholtz and Rayleigh-Taylor (KH-RT) break models proved to work the best for the investigated injector. Comparisons between various existing spray models and a parametric study have been carried out to study the effects of various spray parameters. The fuel effects have been tested by using three different primary reference fuel (PRF

  6. The safe operation zone of the spark ignition engine working with dual renewable supplemented fuels (hydrogen+ethyl alcohol)

    Energy Technology Data Exchange (ETDEWEB)

    Al-Baghdadi, Maher Abdul-Resul Sadiq [Babylon Univ., Dept. of Mechanical Engineering, Babylon (Iraq)

    2001-04-01

    The effect of the amount of hydrogen/ethyl alcohol addition on the performance and pollutant emission of a four-stroke spark ignition engine has been studied. The results of the study show that all engine performance parameters have been improved when operating the gasoline spark ignition engine with dual addition of hydrogen and ethyl alcohol. The important improvements of alcohol addition are to reduce the NOx emission while increasing the higher useful compression ratio and output power of hydrogen-supplemented engine. An equation has been derived from experimental data to specify the least quantity of ethyl alcohol blended with gasoline and satisfying constant NOx emission when hydrogen is added. A chart limiting the safe operation zone of the engine fueled with dual renewable supplemented fuel, (hydrogen and ethyl alcohol) has been produced. The safe zone provides lower NOx and CO emission, lower s.f.c. and higher brake power compared to an equivalent gasoline engine. When ethyl alcohol is increased over 30%, it causes unstable engine operation which can be related to the fact that the fuel is not vaporized, and this causes a reduction in both brake power and efficiency. (Author)

  7. An experimental assessment on the influence of high octane fuels on biofuel based dual fuel engine performance, emission, and combustion

    Directory of Open Access Journals (Sweden)

    Masimalai Senthilkumar

    2017-01-01

    Full Text Available This paper presents an experimental study on the effect of different high octane fuels (such as eucalyptus oil, ethanol, and methanol on engine’s performance behaviour of a biofuel based dual fuel engine. A single cylinder Diesel engine was modified and tested under dual fuel mode of operation. Initially the engine was run using neat diesel, neat mahua oil as fuels. In the second phase, the engine was operated in dual fuel mode by using a specially designed variable jet carburettor to supply the high octane fuels. Engine trials were made at 100% and 40% loads (power outputs with varying amounts of high octane fuels up-to the maximum possible limit. The performance and emission characteristics of the engine were obtained and analysed. Results indicated significant improvement in brake thermal efficiency simultaneous reduction in smoke and NO emissions in dual fuel operation with all the inducted fuels. At 100% load the brake thermal efficiency increased from 25.6% to a maximum of 32.3, 30.5, and 28.4%, respectively, with eucalyptus oil, ethanol, and methanol as primary fuels. Smoke was reduced drastically from 78% with neat mahua oil a minimum of 41, 48, and 53%, respectively, with eucalyptus oil, ethanol, and methanol at the maximum efficiency point. The optimal energy share for the best engine behaviour was found to be 44.6, 27.3, and 23.2%, respectively, for eucalyptus oil, ethanol, and methanol at 100% load. Among the primary fuels tested, eucalyptus oil showed the maximum brake thermal efficiency, minimum smoke and NO emissions and maximum energy replacement for the optimal operation of the engine.

  8. Assessment of maximum available work of a hydrogen fueled compression ignition engine using exergy analysis

    International Nuclear Information System (INIS)

    Chintala, Venkateswarlu; Subramanian, K.A.

    2014-01-01

    This work is aimed at study of maximum available work and irreversibility (mixing, combustion, unburned, and friction) of a dual-fuel diesel engine (H 2 (hydrogen)–diesel) using exergy analysis. The maximum available work increased with H 2 addition due to reduction in irreversibility of combustion because of less entropy generation. The irreversibility of unburned fuel with the H 2 fuel also decreased due to the engine combustion with high temperature whereas there is no effect of H 2 on mixing and friction irreversibility. The maximum available work of the diesel engine at rated load increased from 29% with conventional base mode (without H 2 ) to 31.7% with dual-fuel mode (18% H 2 energy share) whereas total irreversibility of the engine decreased drastically from 41.2% to 39.3%. The energy efficiency of the engine with H 2 increased about 10% with 36% reduction in CO 2 emission. The developed methodology could also be applicable to find the effect and scope of different technologies including exhaust gas recirculation and turbo charging on maximum available work and energy efficiency of diesel engines. - Highlights: • Energy efficiency of diesel engine increases with hydrogen under dual-fuel mode. • Maximum available work of the engine increases significantly with hydrogen. • Combustion and unburned fuel irreversibility decrease with hydrogen. • No significant effect of hydrogen on mixing and friction irreversibility. • Reduction in CO 2 emission along with HC, CO and smoke emissions

  9. Design and multifidelity analysis of dual mode scramjet compression system using coupled NPSS and fluent simulation

    Science.gov (United States)

    Vijayakumar, Nandakumar

    Hypersonic airbreathing engines mark a potential future development of the aerospace industry and immense efforts have been taken in gaining knowledge in them for the past decades. The physical phenomenon occurring at the hypersonic flow regime makes the design and performance prediction of a scramjet engine hard. Though cutting-edge simulation tools fight their way toward accurate prediction of the environment, the time consumed by the entire process in designing and analyzing a scramjet engine and its component may be exorbitant. A multi-fidelity approach for designing a scramjet with a cruising Mach number of 6 is detailed in this research where high-order simulations are applied according to the physics involved in the component. Two state-of-the-art simulation tools were used to take the aerodynamic and propulsion disciplines into account for realistic prediction of the individual components as well as the entire scramjet. The specific goal of this research is to create a virtual environment to design and analyze a hypersonic, two-dimensional, planar inlet and isolator to check its operability for a dual-mode scramjet engine. The dual mode scramjet engine starts at a Mach number of 3.5 where it operates as a ramjet and accelerates to Mach 6 to be operated as a scramjet engine. The intercomponent interaction between the compression components with the rest of the engine is studied by varying the fidelity of the numerical simulation according to the complexity of the situation. Efforts have been taken to track the transition Mach number as it switches from ramjet to scramjet. A complete scramjet assembly was built using the Numerical Propulsion Simulation System (NPSS) and the performance of the engine was evaluated for various scenarios. Different numerical techniques were opted for varying the fidelity of the analysis with the highest fidelity consisting of 2D RANS CFD simulation. The interaction between the NPSS elements with the CFD solver is governed by the

  10. Performance and exhaust emissions in a natural-gas fueled dual-fuel engine; Tennen gas dual fuel kikan no seino oyobi haiki tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Shioji, M.; Ishiyama, T.; Shibata, H. [Kyoto Univ., Kyoto (Japan). Inst. of Atomic Energy; Ikegami, M. [Fukui Institute of Technology, Fukui (Japan). Faculty of Engineering

    2000-07-25

    In order to establish the optimum fueling in a natural gas fueled dual fuel engine, tests were made for some operational parameters and their combination on the engine performances and the exhaust emissions. The results show that the gas oil quantity should be increased and gas oil injection timing should be advanced to suppress unburned hydrocarbon emission at middle and low output range, while the quantity should be reduced and the timing should be retarded to avoid onset of knock at high loads. The unburned hydrocarbon emission and the thermal efficiency are improved at the same load avoiding too lean natural gas premixture by restriction of intake charge air. However the improvement is limited because the ignition and initial combustion of pilot diesel fuel is deteriorated when the cylinder pressure is excessively lowered by throttling. The increase in pilot gas oil amount is effective for low-load operation and the adequate combination of throttle control and equivalence ratio ensures low hydrocarbon emission and the thermal efficiency comparable to diesel operation. (author)

  11. Studying the effect of compression ratio on an engine fueled with waste oil produced biodiesel/diesel fuel

    Directory of Open Access Journals (Sweden)

    Mohammed EL_Kassaby

    2013-03-01

    Full Text Available Wasted cooking oil from restaurants was used to produce neat (pure biodiesel through transesterification, and then used to prepare biodiesel/diesel blends. The effect of blending ratio and compression ratio on a diesel engine performance has been investigated. Emission and combustion characteristics was studded when the engine operated using the different blends (B10, B20, B30, and B50 and normal diesel fuel (B0 as well as when varying the compression ratio from 14 to 16 to 18. The result shows that the engine torque for all blends increases as the compression ratio increases. The bsfc for all blends decreases as the compression ratio increases and at all compression ratios bsfc remains higher for the higher blends as the biodiesel percent increase. The change of compression ratio from 14 to 18 resulted in, 18.39%, 27.48%, 18.5%, and 19.82% increase in brake thermal efficiency in case of B10, B20, B30, and B50 respectively. On an average, the CO2 emission increased by 14.28%, the HC emission reduced by 52%, CO emission reduced by 37.5% and NOx emission increased by 36.84% when compression ratio was increased from 14 to 18. In spite of the slightly higher viscosity and lower volatility of biodiesel, the ignition delay seems to be lower for biodiesel than for diesel. On average, the delay period decreased by 13.95% when compression ratio was increased from 14 to 18. From this study, increasing the compression ratio had more benefits with biodiesel than that with pure diesel.

  12. Cow Power: A Case Study of Renewable Compressed Natural Gas as a Transportation Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Mintz, Marianne [Argonne National Lab. (ANL), Argonne, IL (United States); Tomich, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-08-01

    This case study explores the production and use of renewable compressed natural gas (R-CNG)—derived from the anaerobic digestion (AD) of dairy manure—to fuel 42 heavy-duty milk tanker trucks operating in Indiana, Michigan, Tennessee, and Kentucky.

  13. Geometric size optimization and behavior analysis of a dual-cooled annular fuel

    International Nuclear Information System (INIS)

    Deng Yangbin; Wu Yingwei; Zhang Dalin; Tian Wenxi; Qiu Suizheng; Su Guanghui; Zhang Weixu; Wu Junmei

    2014-01-01

    The dual-cooled annular fuel is one of the innovative fuel concepts, which allows substantial power density increase while maintaining safety margins comparing with that used in currently operating PWRs. In this study, a thermal-hydraulic calculation code, on the basis of inner and outer cooling balance theory, was independently developed to optimize the geometric size of dual-cooled annular fuel elements. The optimization results show that the fuel element with the optimal geometric sizes presents fantastic symmetry in temperature distribution. The optimized geometric sizes agree well with the sizes obtained by MIT (Massachusetts Institute of Technology), which on the other side validates the code reliability and accuracy as well. In addition, a thermo-mechanical-burnup coupling code was developed to study the thermodynamic and mechanical characteristics of fuel elements with considering the irradiation and burnup effects. This coupling program was applied to perform the behavior analysis of annular fuels. The calculation results show that, when the power density increases on the order of up to 50%, the dual-cooled annular fuel elements have much lower fuel temperature and much less fission gas release comparing with conventional fuel rods. Furthermore, the results indicate that the thicknesses of inner and outer gas gap cannot remain the same with the burnup increasing due to the mechanical deformations of fuel pellets and claddings, which results in significantly asymmetric temperature distribution especially at the last phase of burnup. (author)

  14. Effect of main injection timing for controlling the combustion phasing of a homogeneous charge compression ignition engine using a new dual injection strategy

    International Nuclear Information System (INIS)

    Das, Pranab; Subbarao, P.M.V.; Subrahmanyam, J.P.

    2015-01-01

    Highlights: • A new dual injection concept is developed by minimum geometry modification. • The occurrence of combustion parameters strongly depend on main injection timing. • At higher load, premixed equivalence ratio dominates over main injection timing. • Retarded of main injection timing tends to retard combustion phasing. • Slightly retarded main injection timing is recommended to avoid intense knocking. - Abstract: Homogeneous charge compression ignition combustion of diesel fuel is implemented using a novel dual injection strategy. A new experimental technique is developed to modify a single cylinder direct injection diesel engine to run on homogeneous combustion mode. Effect of main injection timing is investigated covering a range from 26 to 8 crank angle degrees before top dead center with an interval of 3°. Retarded main injection timing is identified as a control strategy for delaying combustion phasing and a means of controlled combustion phasing of direct injection homogeneous charge compression ignition combustion. Two load conditions were investigated and it was observed that at higher load, start of combustion depends more on fuel air equivalence ratio than main injection timing, whereas at low load, it significantly varies with varying main injection timing. Significant improvements in smoke and oxides of nitrogen emissions are observed when compared with the baseline conventional combustion. By studying different combustion parameters, it is observed that there is an improvement in performance and emissions with marginal loss in thermal efficiency when the main injection timing is 20° before top dead center. This is identified as the optimum main injection timing for such homogeneous combustion under the same operating condition

  15. An examination of the flame spread limits in a dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Badr, O.; Karim, G.A.; Liu, B. [Calgary Univ., Dept. of Mechanical Engineering, Calgary, AB (Canada)

    1999-10-01

    The performance of a gas-fuelled diesel engine (dual fuel) is examined at light load and an effective threshold limit to the combustion of the gaseous fuel through bulk flame spread is identified. The relationship of such a limit to some of the key operating parameters is then discussed. A comparison between the measured values of the limit with those corresponding to the lower flammability limits of the gaseous fuel when evaluated under the prevailing cylinder conditions during pilot diesel fuel ignition showed similar trends. It is suggested that such a similarity may form a basis for estimating the lean operation limits for duel a fuel combustion in engines. A simple approach for estimating the limiting equivalence ratio for the apparent bulk flame spread limit is described for a methane-fuelled dual fuel engine. (Author)

  16. Possibility to Increase Biofuels Energy Efficiency used for Compression Ignition Engines Fueling

    Directory of Open Access Journals (Sweden)

    Calin D. Iclodean

    2014-02-01

    Full Text Available The paper presents the possibilities of optimizing the use of biofuels in terms of energy efficiency in compression ignition (CI engines fueling. Based on the experimental results was determinate the law of variation of the rate of heat released by the combustion process for diesel fuel and different blends of biodiesel. Using this law, were changed parameters of the engine management system (fuel injection law and was obtain increased engine performance (in terms of energy efficiency for use of different biofuel blends.

  17. Emission and operating performance of a biomethane tractor with dual fuel engine

    International Nuclear Information System (INIS)

    Mautner, Sebastian; Emberger, Peter; Thuneke, Klaus; Remmele, Edgar

    2016-01-01

    The use of biomethane as fuel for agricultural machinery with dual fuel technology is contributing to climate protection and ensures safe fuel supply. So far, hardly any documented operational experiences are known. The aim of the project, funded by the Bavarian Ministry of Economic Affairs and Media, Energy and Technology, was to investigate practicability for daily use and the emission behaviour of a Valtra N101 prototype tractor (exhaust stage IIIA). The retrofitted dual-fuel technology of the former conventional diesel tractor simultaneously uses biomethane or natural gas and diesel as ignition fuel. During the field test over 590 working hours, the tractor showed overall high reliability. On average the operating range in dual-fuel mode with one complete filling of the gas tanks was about 11.5 hours. On the tractor test bench a significant improvement of the exhaust emissions could be observed, since the gas ECU had been optimized and changed by the manufacturer. For dual-fuel operation, nitrogen oxides (NO x ) are lower, whereas carbon monoxide (CO), hydrocarbons (HC) and particulate matter emissions (PM) are higher compared to solely diesel operation. In particular, HC emissions exceed the proposed limiting value, submitted by the European Commission. This is due to incomplete gas combustion and insufficient conversion by the exhaust after-treatment-system (methane slip). A big potential for optimization is expected by adjusting the operating point-specific gasdiesel ratio and improving the exhaust gas aftertreatment system.

  18. Comparison of performance of biodiesels of mahua oil and gingili oil in dual fuel engine

    Directory of Open Access Journals (Sweden)

    Nadar Kapilan N.

    2008-01-01

    Full Text Available In this work, an experimental work was carried out to compare the performance of biodiesels made from non edible mahua oil and edible gingili oil in dual fuel engine. A single cylinder diesel engine was modified to work in dual fuel mode and liquefied petroleum gas was used as primary fuel. Biodiesel was prepared by transesterification process and mahua oil methyl ester (MOME and gingili oil methyl ester (GOME were used as pilot fuels. The viscosity of MOME is slightly higher than GOME. The dual fuel engine runs smoothly with MOME and GOME. The test results show that the performance of the MOME is close to GOME, at the pilot fuel quantity of 0.45 kg/h and at the advanced injection timing of 30 deg bTDC. Also it is observed that the smoke, carbon monoxide and unburnt hydro carbon emissions of GOME lower than the MOME. But the GOME results in slightly higher NOx emissions. From the experimental results it is concluded that the biodiesel made from mahua oil can be used as a substitute for diesel in dual fuel engine.

  19. On the effects of fuel properties and injection timing in partially premixed compression ignition of low octane fuels

    KAUST Repository

    Naser, Nimal

    2017-06-29

    A better understanding on the effects of fuel properties and injection timing is required to improve the performance of advanced engines based on low temperature combustion concepts. In this work, an experimental and computational study was conducted to investigate the effects of physical and chemical kinetic properties of low octane fuels and their surrogates in partially premixed compression ignition (PPCI) engines. The main objective was to identify the relative importance of physical versus chemical kinetic properties in predicting practical fuel combustion behavior across a range of injection timings. Two fuel/surrogate pairs were chosen for comparison: light naphtha (LN) versus the primary reference fuel (PRF) with research octane number of 65 (PRF 65), and FACE (fuels for advanced combustion engines) I gasoline versus PRF 70. Two sets of parametric studies were conducted: the first varied the amount of injected fuel mass at different injection timings to match a fixed combustion phasing, and the second maintained the same injected fuel mass at each injection timing to assess resulting combustion phasing changes. Full-cycle computational fluid dynamic engine simulations were conducted by accounting for differences in the physical properties of the original and surrogate fuels, while employing identical chemical kinetics. The simulations were found to capture trends observed in the experiments, while providing details on spatial mixing and chemical reactivity for different fuels and injection timings. It was found that differences in physical properties become increasingly important as injection timing was progressively delayed from premixed conditions, and this was rationalized by analysis of mixture stratification patterns resulting from injection of fuels with different physical properties. The results suggest that accurate descriptions of both physical and chemical behavior of fuels are critical in predictive simulations of PPCI engines for a wide range of

  20. On the effects of fuel properties and injection timing in partially premixed compression ignition of low octane fuels

    KAUST Repository

    Naser, Nimal; Jaasim, Mohammed; Atef, Nour; Chung, Suk-Ho; Im, Hong G.; Sarathy, Mani

    2017-01-01

    A better understanding on the effects of fuel properties and injection timing is required to improve the performance of advanced engines based on low temperature combustion concepts. In this work, an experimental and computational study was conducted to investigate the effects of physical and chemical kinetic properties of low octane fuels and their surrogates in partially premixed compression ignition (PPCI) engines. The main objective was to identify the relative importance of physical versus chemical kinetic properties in predicting practical fuel combustion behavior across a range of injection timings. Two fuel/surrogate pairs were chosen for comparison: light naphtha (LN) versus the primary reference fuel (PRF) with research octane number of 65 (PRF 65), and FACE (fuels for advanced combustion engines) I gasoline versus PRF 70. Two sets of parametric studies were conducted: the first varied the amount of injected fuel mass at different injection timings to match a fixed combustion phasing, and the second maintained the same injected fuel mass at each injection timing to assess resulting combustion phasing changes. Full-cycle computational fluid dynamic engine simulations were conducted by accounting for differences in the physical properties of the original and surrogate fuels, while employing identical chemical kinetics. The simulations were found to capture trends observed in the experiments, while providing details on spatial mixing and chemical reactivity for different fuels and injection timings. It was found that differences in physical properties become increasingly important as injection timing was progressively delayed from premixed conditions, and this was rationalized by analysis of mixture stratification patterns resulting from injection of fuels with different physical properties. The results suggest that accurate descriptions of both physical and chemical behavior of fuels are critical in predictive simulations of PPCI engines for a wide range of

  1. KAJIAN TEKNIS DAN EKONOMIS PENGGUNAAN DUAL FUEL SYSTEM (LPG-SOLAR PADA MESIN DIESEL KAPAL NELAYAN TRADISIONAL

    Directory of Open Access Journals (Sweden)

    Imam Pujo Mulyatno

    2013-06-01

    Full Text Available Pengembangan bahan bakar alternatif dalam rangka mengurangi ketergantungan terhadap bahan bakar minyak (BBM, telah menjadi agenda penting  pemerintah. Penggunaan LPG (Liquefied Petrolium Gas pada mesin diesel kapal nelayan tradisional didasarkan pada keberhasilan penggunaan LPG pada kendaraan-kendaraan darat. Penggunaan LPG pada mesin diesel dilakukan secara dual fuel. Penelitian dual fuel system pada mesin diesel kapal nelayan tradisional bertujuan untuk mengetahui pengaruh penggunaan bahan bakar dual fuel terhadap kinerja mesin dan sistem penggeraknya, meliputi konsumsi bahan bakar, daya, kecepatan kapal, serta efisiensi pada sistem penggerak kapal. Penelitian dilakukan dengan menggunakan DongFeng ZS-1100 dengan tiga putaran mesin yang berbeda yaitu 1000rpm, 1250 rpm dan 1500 rpm. Berdasarkan hasil penelitian ini, penggunaan LPG secara dual fuel mampu menggantikan konsumsi solar hingga 71% dari konsumsi solar seluruhnya selama satu jam. Komposisi LPG yang dihasilkan mencapai lebih dari 60%  dari total pemakaian bahan bakar saat dual fuel. Kecepatan dan jarak tempuh saat menggunakan solar seluruhnya mencapai 5% lebih tinggi dibandingkan dual fuel. Daya dan torsi saat menggunakan dual fuel mencapai 9,8 % lebih tinggi dibandingkan solar seluruhnya. Penggunaan dual fuel mampu mengurangi biaya operasional penangkapan ikan hingga 24,6%, namun dengan waktu tempuh 1,3% lebih lama dari solar seluruhnya. Efisiensi propulsi solar seluruhnya 6% lebih besar dibandingkan efisiensi propulsi dual fuel.

  2. Integrated modeling for optimized regional transportation with compressed natural gas fuel

    Directory of Open Access Journals (Sweden)

    Hossam A. Gabbar

    2016-03-01

    Full Text Available Transportation represents major energy consumption where fuel is considered as a primary energy source. Recent development in the vehicle technology revealed possible economical improvements when using natural gas as a fuel source instead of traditional gasoline. There are several fuel alternatives such as electricity, which showed potential for future long-term transportation. However, the move from current situation where gasoline vehicle is dominating shows high cost compared to compressed natural gas vehicle. This paper presents modeling and simulation methodology to optimize performance of transportation based on quantitative study of the risk-based performance of regional transportation. Emission estimation method is demonstrated and used to optimize transportation strategies based on life cycle costing. Different fuel supply scenarios are synthesized and evaluated, which showed strategic use of natural gas as a fuel supply.

  3. Investigation on parameters of methanol fuel and its blend on a diesel dual fuel engine

    Directory of Open Access Journals (Sweden)

    G. K. Prashant

    2016-06-01

    Full Text Available An experimental investigation has been performed on a 4 cylinder (turbocharged and intercooled 62.5 kW gen-set dual fuel diesel engine. Break specific fuel consumption (bsfc, break thermal efficiency (bte along with HC, CO, CO2 and NOx at various mixture ratios of methanol substitutions and loads have been investigated. The minimum and maximum BSFC were found to be 0.18 and 1.01 at 40 and 10% of full engine load and 40 and 60% of methanol substitution compared to pure diesel operation where the minimum and maximum BSFC were found to be 0.26 and 0.434 at 20 and 10% of full load condition. The minimum and maximum BTE were found to be 7.19 and 40.8 at 60 and 40% methanol substitution and at 10 and 40% load conditions whilst for pure diesel operation it was found to be 19.7 and 40.4 at 10 and 40% load conditions respectively. A two factor, three-level full factorial design was employed and the experimental results are in accordance with the results obtained.

  4. Wartsila 32DF, the dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1999-06-01

    This paper gives details of the development of the Wartsila 32DF duel-fuel lean-burn engine that can burn liquid or gaseous fuels, and reports on the installation of four of the engines in Turkey. The combustion process, and the design of the gas admission, pilot fuel, cylinder control, air-fuel control, and engine control and monitoring systems are described. The advantages of the engine are discussed.

  5. Greenhouse Gas and Noxious Emissions from Dual Fuel Diesel and Natural Gas Heavy Goods Vehicles.

    Science.gov (United States)

    Stettler, Marc E J; Midgley, William J B; Swanson, Jacob J; Cebon, David; Boies, Adam M

    2016-02-16

    Dual fuel diesel and natural gas heavy goods vehicles (HGVs) operate on a combination of the two fuels simultaneously. By substituting diesel for natural gas, vehicle operators can benefit from reduced fuel costs and as natural gas has a lower CO2 intensity compared to diesel, dual fuel HGVs have the potential to reduce greenhouse gas (GHG) emissions from the freight sector. In this study, energy consumption, greenhouse gas and noxious emissions for five after-market dual fuel configurations of two vehicle platforms are compared relative to their diesel-only baseline values over transient and steady state testing. Over a transient cycle, CO2 emissions are reduced by up to 9%; however, methane (CH4) emissions due to incomplete combustion lead to CO2e emissions that are 50-127% higher than the equivalent diesel vehicle. Oxidation catalysts evaluated on the vehicles at steady state reduced CH4 emissions by at most 15% at exhaust gas temperatures representative of transient conditions. This study highlights that control of CH4 emissions and improved control of in-cylinder CH4 combustion are required to reduce total GHG emissions of dual fuel HGVs relative to diesel vehicles.

  6. FeCrAl/Zr dual layer fuel cladding for improved safety margin under accident scenario

    International Nuclear Information System (INIS)

    Park, D.J.; Park, J.H.; Jung, Y.I.; Kim, H.G.; Park, J.Y.; Koo, Y.H.

    2014-01-01

    For application of advanced steel as a cladding material in light water reactor (LWR), FeCrAl/Zr dual layer tube was manufactured by using a hot isostatic pressing (HIP) method. To optimize HIP condition for joining both FeCrAl and Zr alloys, HIP was carried out under various temperature conditions. Tensile test and 3-point bend test performed for measuring mechanical properties of HIPed sample. To better understand microstructural characteristics in interface region between two alloys, SEM and TEM study were conducted by using HIPed sample with different process conditions. Based on this optimization study and analyzed results, optimized HIP condition was determined and FeCrAl/Zr dual layer fuel cladding having same wall thickness with current LWR fuel cladding was manufactured. Simulated loss-of-coolant accident test was carried out using FeCrAl/Zr dual layer cladding sample and fuel integrity was measured by mechanical test. (authors)

  7. The influence of Compression Ratio to Performance of Four Stroke Engine Use of Arak Bali as a Fuel

    Directory of Open Access Journals (Sweden)

    I Dewa Made Krishna Muku

    2012-11-01

    Full Text Available Arak bali is alternative fuel as ethanol. Ethanol has octane number 108. Octane number which was higher can over come adetonation, and can work at higher compression ratio. This experiment has done to now how the effect of compression ratiovariation to the performance four strokes engine by arak bali fuel. This research was done by changing the compressionratio that is 8,8 : 1, 8,9 : 1, 9 : 1 and 9,3 : 1. The change was done by reducing combustion chamber by scrap the cylinderhead. The result, for the used arak bali fuel to the vehicle is, if engine compression ratio to increase can be influence ofengine performance to be increase and engine fuel consumption to be decrease. For premium is, if engine compression ratioto increase to influence of engine performance to be decrease and engine fuel consumption to be increase.

  8. The use of modified tyre derived fuel for compression ignition engines.

    Science.gov (United States)

    Pilusa, T J

    2017-02-01

    This study investigated physical and chemical modification of tyre-derived fuel oil (TDFO) obtained from pyrolysis of waste tyres and rubber products for application as an alternative fuel for compression ignition engines (CIE's). TDFO collected from a local waste tyre treatment facility was refined via a novel "oxidative gas-phase fractional distillation over 13× molecular sieves" to recover the light to medium fractions of the TDFO while oxidising and capturing some sulphur compounds in a gas phase. This was followed by desulphurization and chemical modification to improve cetane number, kinematic viscosity and fuel stability. The resulting fuel was tested in an ADE407T truck engine to compare its performance with petroleum diesel fuel. It was discovered that gas phase oxidative fractional distillation reduces the low boiling point sulphur compounds in TDFO such as mercaptans. Using petroleum diesel fuel as a reference, it was observed that the produced fuel has a lower cetane number, flash point and viscosity. On storage the fuel tends to form fibrous microstructures as a result of auto-oxidation of asphaltenes present in the fuel. Mixtures of alkyl nitrate, vinyl acetate, methacrylic anhydride, methyl-tert butyl ether, n-hexane and n-heptane were used to chemically modify the fuel in accordance with the minimum fuel specifications as per SANS 342. The engine performance tests results did not show any sign of engine ceasing or knocking effect. The power-torque trend was very consistent and compared well with petroleum diesel fuelled engine. The levels of total sulphur are still considerably high compared to other cleaner fuel alternatives derived from zero sulphur sources. Copyright © 2016. Published by Elsevier Ltd.

  9. Spray-Wall Impingement of Diesel-CNG Dual Fuel Jet using Schlieren Imaging Technique

    Directory of Open Access Journals (Sweden)

    Ismael Mhadi Abaker

    2014-07-01

    Full Text Available Natural gas is a low cost fuel with high availability in nature. However, it cannot be used by itself in conventional diesel engines due to its low flame speed and high ignition temperature. The addition of a secondary fuel to enhance the mixture formation and combustion process facilitate its wider use as an alternative fuel. An experimental study was performed to investigate the diesel-CNG dual fuel jet-wall impingement. A constant volume optical chamber was designed to facilitate maximum optical access for the study of the jet-wall impingement at different injection pressures, temperatures and injector-wall distances. The bottom plate of the test rig was made of aluminum (piston material and it was heated up to 500 K at ambient pressure. An injector driver was used to control the single-hole nozzle diesel injector combined with a natural gas injector. The injection timing of both injectors was synchronized with a camera trigger. The jet-wall impingement of diesel and diesel-CNG dual fuel jets was recorded with a high speed camera using Schlieren imaging technique and associated image processing software. The measurements of the jet radial penetration were higher in diesel-CNG dual fuel while the jet height travel along were higher in the case of diesel single fuel.

  10. Analysis of a combustion, performance and emission characteristics of a CNG-B20 fuelled diesel engine under dual fuel mode

    Directory of Open Access Journals (Sweden)

    Pankaj S. Shelke

    2016-09-01

    Full Text Available The Carbon dioxide (CO2 is one of the primary greenhouse gases emitted by various human activities. CO2 is naturally present in the atmosphere as part of carbon cycle. Human activities are altering the carbon cycle by adding or removing CO2 to the atmosphere. The main human activity that emits the CO2 is combustion of fossil fuels for energy and transportation. Compression ignition (CI engines emit high amount of CO2 emission as it is the end product of complete combustion of hydro carbon fuels. Moreover, they emit higher NOx (nitrogen oxides and PM (particulate matter emissions and have higher fuel consumption. In the present study, experimental investigations were carried out on a CI engine under dual fuel mode with biodiesel as a pilot fuel and compressed natural gas (CNG as a main fuel. The effects of 10 % and 20 % CNG energy shares on performance and emission characteristics of the engine at rated (100% loads were studied. Experimental results indicate the beneficial of CNG addition on improvement in the engine efficiency, and reduction in NOx and CO2 emissions. The NOx and CO2 emissions decreased by 14.24 % and 30 % respectively at the rated load with biodiesel + CNG (20 % energy share as compared to base diesel. No knocking combustion was observed during the tests which confirm the smooth operation. The dual fuel operation with combination of CNG-biodiesel is an effective method to reduce NOx and CO2 emissions with an additional benefit of lower specific energy consumption.

  11. Alternative Fuel Vehicles: The Case of Compressed Natural Gas (CNG) Vehicles in California Households

    OpenAIRE

    Abbanat, Brian A.

    2001-01-01

    Compressed natural gas (CNG) vehicles have been used internationally by fleets and households for decades. The use of CNG vehicles results in less petroleum consumption, and fewer air pollutant and greenhouse gas emissions in most applications. In the United States, the adoption of CNG technology has been slowed by the availability of affordable gasoline and diesel fuel. This study addresses the potential market for CNG vehicles at the consumer level in California. Based on semi-structured pe...

  12. Development of Test Methods for Structural Components of a Dual Cooled Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Ho; Lee, Kang Hee; Kim, Hyung Kyu; Yoon, Kyung Ho; Kim, Jae Yong

    2009-01-15

    The most unique feature of a dual-cooled fuel is that the outer diameter of a fuel rod is considerably increased due to an internal coolant passage additionally formed inside the rod. This increases the fuel rod's weight and decreases the gap between the fuel rods. Change of the weight and gap causes the shape and the performance of a fuel rod support structure to be necessarily altered. It also alters the flow-induced vibration (FIV) as well as the fretting wear characteristics of a fuel rod. These are directly related with the integrity of the rod so that they should be investigated in the design stage. Finite element analysis and semi-empirical formulae can be used to roughly investigate the support performance and FIV of a fuel rod, respectively. However, the fretting wear characteristic can be investigated only through an experiment. The support performance and FIV need experiment as well to obtain the characteristics more accurately. Therefore, experimental investigation of those has been included in the present project scope. In the second year, it has been planned to establish the experimental devices and technologies to accommodate the altered dimensions and feature of a dual-cooled fuel. As a result, devices to obtain the characteristics of fuel rod supports and holddown springs were developed. As for the FIV and fretting wear characteristics, the existing facilities were modified. Experimental procedures were also re-established this year.

  13. Systems studies of dual purpose electric/synthetic fuels fusion plants

    International Nuclear Information System (INIS)

    Beardsworth, E.; Powell, J.

    1975-02-01

    A reactor power plant is proposed that can meet base load electrical demand, while the remainder can generate synthetic fuels and meet intermittent electrical demands. Two principal objectives of this study are: (1) to examine how strongly various economic demand and resource factors affect the amount of installed CTR capacity, and (2) to examine what increase in CTR capacity can be expected with dual purpose electric/synthetic fuel fusion plants, and also the relative importance of the different production modes

  14. Compressive strength and microstructural analysis of fly ash/palm oil fuel ash based geopolymer mortar

    International Nuclear Information System (INIS)

    Ranjbar, Navid; Mehrali, Mehdi; Behnia, Arash; Alengaram, U. Johnson; Jumaat, Mohd Zamin

    2014-01-01

    Highlights: • Results show POFA is adaptable as replacement in FA based geopolymer mortar. • The increase in POFA/FA ratio delay of the compressive development of geopolymer. • The density of POFA based geoploymer is lower than FA based geopolymer mortar. - Abstract: This paper presents the effects and adaptability of palm oil fuel ash (POFA) as a replacement material in fly ash (FA) based geopolymer mortar from the aspect of microstructural and compressive strength. The geopolymers developed were synthesized with a combination of sodium hydroxide and sodium silicate as activator and POFA and FA as high silica–alumina resources. The development of compressive strength of POFA/FA based geopolymers was investigated using X-ray florescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and field emission scanning electron microscopy (FESEM). It was observed that the particle shapes and surface area of POFA and FA as well as chemical composition affects the density and compressive strength of the mortars. The increment in the percentages of POFA increased the silica/alumina (SiO 2 /Al 2 O 3 ) ratio and that resulted in reduction of the early compressive strength of the geopolymer and delayed the geopolymerization process

  15. A Novel Hybrid-Fuel Storage System of Compressed Air Energy for China

    Directory of Open Access Journals (Sweden)

    Wenyi Liu

    2014-08-01

    Full Text Available Compressed air energy storage (CAES is a large-scale technology that provides long-duration energy storage. It is promising for balancing the large-scale penetration of intermittent and dispersed sources of power, such as wind and solar power, into electric grids. The existing CAES plants utilize natural gas (NG as fuel. However, China is rich in coal but is deficient in NG; therefore, a hybrid-fuel CAES is proposed and analyzed in this study. Based on the existing CAES plants, the hybrid-fuel CAES incorporates an external combustion heater into the power generation subsystem to heat the air from the recuperator and the air from the high-pressure air turbine. Coal is the fuel for the external combustion heater. The overall efficiency and exergy efficiency of the hybrid-fuel CAES are 61.18% and 59.84%, respectively. Given the same parameters, the cost of electricity (COE of the hybrid-fuel CAES, which requires less NG, is $5.48/MW∙h less than that of the gas-fuel CAES. Although the proposed CAES requires a relatively high investment in the current electricity system in North China, the proposed CAES will be likely to become competitive in the market, provided that the energy supplies are improved and the large scale grid-connection of wind power is realized.

  16. Concept for a LNG Gas Handling System for a Dual Fuel Engine

    Directory of Open Access Journals (Sweden)

    Michael Rachow

    2017-09-01

    Full Text Available Nowadays, ships are using LNG as main engine fuel because based on the facts that LNG has no sulphur content, and its combustion process, LNG produces low NOx content compared to heavy fuel oil and marine diesel oil. LNG is not only produces low gas emission, but may have economic advantages. In the engine laboratory of maritime studies department in Warnemunde, Germany, there is a diesel engine type MAN 6L23/30 A, where the mode operation of these engine would be changed to dual fuel engine mode operation. Therefore, in this thesis, the use dual fuel engine will be compared where it will utilize natural gas and marine diesel oil and select the required components for fuel gas supply system. By conducting the process calculation, engine MAN 6L23/30 A requires the capacity natural gas of 12.908  for 5 days at full load. A concept for LNG supply system would be arranged from storage tank until engine manifold. Germanischer Lloyd and Project Guide of dual fuel engine will be used as a guidelines to develop an optimal design and arrangement which comply with the regulation.

  17. Future combustion technology for synthetic and renewable fuels in compression ignition engines (REFUEL). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Aakko-Saksa, P.; Brink, A.; Happonen, M. [and others

    2012-07-01

    This domestic project, Future Combustion Technology for Synthetic and Renewable Fuels in Compression Ignition Engines (ReFuel), was part of a Collaborative Task 'Future Combustion Technology for Synthetic and Renewable Fuels in Transport' of International Energy Agency (IEA) Combustion Agreement. This international Collaborative Task is coordinated by Finland. The three-year (2009-2011) prooject was a joint research project with Aalto University (Aalto), Tampere University of Technology (TUT), Technical Research Centre of Finland (VTT) and Aabo Akademi University (AAU). The project was funded by TEKES, Waertsilae Oyj, Agro Sisu Power, Aker Arctic Technology Oy and the research partners listed above. Modern renewable diesel fuels have excellent physical and chemical properties, in comparison to traditional crude oil based fuels. Purely paraffinic fuels do not contain aromatic compounds and they are totally sulphur free. Hydrotreated Vegetable Oil (HVO) was studied as an example of paraffinic high cetane number (CN) diesel fuels. HVO has no storage and low temperature problems like the fatty acid methyl esters (FAMEs) have. The combustion properties are better than those of crude oil based fuels and FAME, because they have very high cetane numbers and contain no polyaromatic hydrocarbons (PAH). With low HVO density, viscosity and distillation temperatures, these advantageous properties allow far more advanced combustion strategies, such as very high exhaust gas recirculation (EGR) rates or extreme Miller timings, than has been possible with current fossil fuels. The implementation of these advanced combustion technologies, together with the novel renewable diesel fuel, brought significant nitrogen oxides (NO{sub x}), particulate matter (PM) emission reductions with no efficiency losses. (orig.)

  18. Physical and chemical effects of low octane gasoline fuels on compression ignition combustion

    KAUST Repository

    Badra, Jihad

    2016-09-30

    Gasoline compression ignition (GCI) engines running on low octane gasoline fuels are considered an attractive alternative to traditional spark ignition engines. In this study, three fuels with different chemical and physical characteristics have been investigated in single cylinder engine running in GCI combustion mode at part-load conditions both experimentally and numerically. The studied fuels are: Saudi Aramco light naphtha (SALN) (Research octane number (RON) = 62 and final boiling point (FBP) = 91 °C), Haltermann straight run naphtha (HSRN) (RON = 60 and FBP = 140 °C) and a primary reference fuel (PRF65) (RON = 65 and FBP = 99 °C). Injection sweeps, where the start of injection (SOI) is changed between −60 and −11 CAD aTDC, have been performed for the three fuels. Full cycle computational fluid dynamics (CFD) simulations were executed using PRFs as chemical surrogates for the naphtha fuels. Physical surrogates based on the evaporation characteristics of the naphtha streams have been developed and their properties have been implemented in the engine simulations. It was found that the three fuels have similar combustion phasings and emissions at the conditions tested in this work with minor differences at SOI earlier than −30 CAD aTDC. These trends were successfully reproduced by the CFD calculations. The chemical and physical effects were further investigated numerically. It was found that the physical characteristics of the fuel significantly affect the combustion for injections earlier than −30 CAD aTDC because of the low evaporation rates of the fuel because of the higher boiling temperature of the fuel and the colder in-cylinder air during injection. © 2016 Elsevier Ltd

  19. Jatropha oil and biogas in a dual fuel CI engine for rural electrification

    NARCIS (Netherlands)

    Luijten, C.C.M.; Kerkhof, E.

    2011-01-01

    This work presents the first dual fuel measurements with pure jatropha oil and biogas, using a 12 kW diesel engine generator. Reference tests are done with pure jatropha oil and with diesel to characterize the engine’s thermal efficiency eta_t, volumetric efficiency eta_v and air excess ratio lambda

  20. Dual arm master controller concept: consolidated fuel reprocessing program

    International Nuclear Information System (INIS)

    Kuban, D.P.; Perkins, G.S.

    1984-04-01

    The Advanced Servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features result in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. 6 references, 3 figures

  1. Combustion characteristics of a turbocharged DI compression ignition engine fueled wth petroleum diesel fuels and biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Canakci, M. [Kocaeli University, Izmit (Turkey). Department of Mechanical Education

    2007-04-15

    In this study, the combustion characteristics and emissions of two different petroleum diesel fuels (No. 1 and No. 2) and biodiesel from soybean oil were compared. The tests were performed at steady state conditions in a four-cylinder turbocharged DI diesel engine at full load at 1400-rpm engine speed. The experimental results compared with No. 2 diesel fuel showed that biodiesel provided significant reductions in PM, CO, and unburned HC, the NO{sub x} increased by 11.2%. Biodiesel had a 13.8% increase in brake-specific fuel consumption due to its lower heating value. However, using No. 1 diesel fuel gave better emission results, NO{sub x} and brake-specific fuel consumption reduced by 16.1% and 1.2%, respectively. The values of the principal combustion characteristics of the biodiesel were obtained between two petroleum diesel fuels. The results indicated that biodiesel may be blended with No. 1 diesel fuel to be used without any modification on the engine. (author)

  2. Burn characteristics of compressed fuel pellets for D-3He inertial fusion

    International Nuclear Information System (INIS)

    Nakao, Y.; Honda, T.; Honda, Y.; Kudo, K.; Nakashima, H.

    1992-01-01

    In this paper, the feasibility of using D- 3 He fuel in inertial confinement fusion is examined by using a hydrodynamics code that includes neutron and charged-particle transport routines. The use of a small amount of deuterium-tritium (D-T) ignitor is indispensable. Burn simulations are made for quasi-isobaric D-T/D- 3 He pellet models compressed to 5000 times the liquid density. Substantial fuel gains (∼500) are obtained from pellets having parameters ρR D-T = 3 g/cm 2 and ρR total = 14 g/cm 2 and a central spark temperature of 5 keV. The amount of driver energy needed to achieve these gains is estimated to be ∼ 30 MJ when the coupling efficiency is 10%. The driver energy requirement can be reduced by using spin-polarized D-T and D- 3 He fuels

  3. Efficiency and exhaust gas analysis of variable compression ratio spark ignition engine fuelled with alternative fuels

    Energy Technology Data Exchange (ETDEWEB)

    Seshaiah, N. [Mechanical Engineering Department, M.I.T.S, Madanapalle, Angallu-517325, A.P. (India)

    2010-07-01

    Considering energy crises and pollution problems today, investigations have been concentrated on decreasing fuel consumption by using alternative fuels and on lowering the concentration of toxic components in combustion products. In the present work, the variable compression ratio spark ignition engine designed to run on gasoline has been tested with pure gasoline, LPG (Isobutene), and gasoline blended with ethanol 10%, 15%, 25% and 35% by volume. Also, the gasoline mixed with kerosene at 15%, 25% and 35% by volume without any engine modifications has been tested and presented the result. Brake thermal and volumetric efficiency variation with brake load is compared and presented. CO and CO2 emissions have been also compared for all tested fuels.

  4. Fuel Vaporization and Its Effect on Combustion in a High-Speed Compression-Ignition Engine

    Science.gov (United States)

    Rothrock, A M; Waldron, C D

    1933-01-01

    The tests discussed in this report were conducted to determine whether or not there is appreciable vaporization of the fuel injected into a high-speed compression-ignition engine during the time available for injection and combustion. The effects of injection advance angle and fuel boiling temperature were investigated. The results show that an appreciable amount of the fuel is vaporized during injection even though the temperature and pressure conditions in the engine are not sufficient to cause ignition either during or after injection, and that when the conditions are such as to cause ignition the vaporization process affects the combustion. The results are compared with those of several other investigators in the same field.

  5. Prediction of major pollutants emission in direct injection dual-fuel diesel and natural-gas engines

    International Nuclear Information System (INIS)

    Pirouzpanah, V.; Kashani, B.O.

    2000-01-01

    The dual-fuel diesel engine is a conventional diesel engine in which much of the energy released, hence power, comes from the combustion of gaseous fuel such as natural gas. The exhaust emission characteristics of the dual-fuel diesel engine needs further refinements, particularly in terms of reduction of Unburnt Hydrocarbons and Carbon Monoxide (CO) emission, because the concentration of these pollutants are higher than that of the baseline diesel engine. Furthermore, the combustion process in a typical dual-fuel diesel engine tends to be complex, showing combination of the problems encountered both in diesel and spark ignition engines. In this work, a computer code has been modified for simulation of dual-fuel diesel engine combustion process. This model simulates dual-fuel diesel engine combustion by using a Multi-Zone Combustion Model for diesel pilot jet combustion and a conventional spark ignition combustion model for modelling of combustion of premixed gas/air charge. Also, in this model, there are four submodels for prediction of major emission pollutants such as: Unburnt Hydrocarbons, No, Co and soot which are emitted from dual-fuel diesel engine. For prediction of formation and oxidation rates of pollutants, relevant s conventional kinetically-controlled mechanisms and mass balances are used. the model has been verified by experimental data obtained from a heavy-duty truck and bus diesel engines. The comparison shows that, there exist good agreements between the experimental and predicted results from the dual-fuel diesel engine

  6. Studies on dual fuel operation of rubber seed oil and its bio-diesel with hydrogen as the inducted fuel

    Energy Technology Data Exchange (ETDEWEB)

    Edwin Geo, V.; Nagalingam, B. [Department of Mechanical Engineering, KCG College of Technology, Chennai, Tamil Nadu 600097 (India); Nagarajan, G. [Department of Mechanical Engineering, IC Engineering Division, Anna University, Chennai, Tamil Nadu 600025 (India)

    2008-11-15

    The main problems with the use of neat vegetable oils in diesel engines are higher smoke levels and lower thermal efficiency as compared to diesel. The problem can be tackled by inducting a gaseous fuel in the intake manifold along with air. In this investigation, hydrogen is used as the inducted fuel and rubber seed oil (RSO), rubber seed oil methyl ester (RSOME) and diesel are used as main fuels in a dual fuel engine. A single cylinder diesel engine with rated output of 4.4 kW at 1500 rpm was converted to operate in the dual fuel mode. Dual fuel operation of varying hydrogen quantity with RSO and RSOME results in higher brake thermal efficiency and significant reduction in smoke levels at high outputs. The maximum brake thermal efficiency is 28.12%, 29.26% and 31.62% with RSO, RSOME and diesel at hydrogen energy share of 8.39%, 8.73% and 10.1%, respectively. Smoke is reduced from 5.5 to 3.5 BSU with RSOME and for RSO it is from 6.1 to 3.8 BSU at the maximum efficiency point. The peak pressure and maximum rate of pressure rise increase with hydrogen induction. Heat release rate indicates an increase in the combustion rate with hydrogen induction. On the whole it is concluded that hydrogen can be inducted along with air in order to reduce smoke levels and improve thermal efficiency of RSO and its bio-diesel fuelled diesel engines. (author)

  7. Applicability of dimethyl ether (DME) in a compression ignition engine as an alternative fuel

    International Nuclear Information System (INIS)

    Park, Su Han; Lee, Chang Sik

    2014-01-01

    Highlights: • Overall characteristics of DME fueled engine are reviewed. • Fuel properties characteristics of DME are introduced. • New technologies for DME vehicle are systemically reviewed. • Research trends for the development of DME vehicle in the world are introduced. - Abstract: From the perspectives of environmental conservation and energy security, dimethyl-ether (DME) is an attractive alternative to conventional diesel fuel for compression ignition (CI) engines. This review article deals with the application characteristics of DME in CI engines, including its fuel properties, spray and atomization characteristics, combustion performance, and exhaust emission characteristics. We also discuss the various technological problems associated with its application in actual engine systems and describe the field test results of developed DME-fueled vehicles. Combustion of DME fuel is associated with low NO x , HC, and CO emissions. In addition, PM emission of DME combustion is very low due to its molecular structure. Moreover, DME has superior atomization and vaporization characteristics than conventional diesel. A high exhaust gas recirculation (EGR) rate can be used in a DME engine to reduce NO x emission without any increase in soot emission, because DME combustion is essentially soot-free. To decrease NO x emission, engine after-treatment devices, such as lean NO x traps (LNTs), urea-selective catalytic reduction, and the combination of EGR and catalyst have been applied. To use DME fuel in automotive vehicles, injector design, fuel feed pump, and the high-pressure injection pump have to be modified, combustion system components, including sealing materials, have to be rigorously designed. To use DME fuel in the diesel vehicles, more research is required to enhance its calorific value and engine durability due to the low lubricity of DME, and methods to reduce NO x emission are also required

  8. Combustion and emissions characteristics of a compression ignition engine fueled with n-butanol blends

    Science.gov (United States)

    Yusri, I. M.; Mamat, R.; Ali, O. M.; Aziz, A.; Akasyah, M. K.; Kamarulzaman, M. K.; Ihsan, C. K.; Mahmadul, H. M.; Rosdi, S. M.

    2015-12-01

    The use of biomass based renewable fuel, n-butanol blends for compression ignition (CI) engine has attracted wide attention due to its superior properties such as better miscibility, higher energy content, and cetane number. In this present study the use of n-butanol 10% blends (Bu10) with diesel fuel has been tested using 4-cylinder, 4-stroke common rail direct injection CI engine to investigate the combustion and emissions of the blended fuels. Based on the tested engine at BMEP=3.5Bar Bu10 fuel indicates lower first and second peak pressure by 5.4% and 2.4% for engine speed 1000rpm and 4.4% and 2.1% for engine speed 2500rpm compared to diesel fuel respectively. Percentage reduction relative to diesel fuel at engine speeds 1000rpm and 2500rpm for Bu10: Exhaust temperature was 7.5% and 5.2% respectively; Nitrogen oxides (NOx) 73.4% and 11.3% respectively.

  9. Study of emissions for a compression ignition engine fueled with a mix of DME and diesel

    Science.gov (United States)

    Jurchiş, Bogdan; Nicolae, Burnete; Călin, Iclodean; Nicolae Vlad, Burnete

    2017-10-01

    Currently, there is a growing demand for diesel engines, primarily due to the relatively low fuel consumption compared to spark-ignition engines. However, these engines have a great disadvantage in terms of pollution because they produce solid particles that ultimately form particulate matter (PM), which has harmful effects on human health and also on the environment. The toxic emissions from the diesel engine exhaust, like particulate matter (PM) and NOx, generated by the combustion of fossil fuels, lead to the necessity to develop green fuels which on one hand should be obtained from regenerative resources and on the other hand less polluting. In this paper, the authors focused on the amount of emissions produced by a diesel engine when running with a fuel mixture consisting of diesel and DME. Dimethyl ether (DME) is developed mainly by converting natural gas or biomass to synthesis gas (syngas). It is an extremely attractive resource for the future used in the transport industry, given that it can be obtained at low costs from renewable resources. Using DME mixed with diesel for the combustion process, besides the fact that it produces less smoke, the emission levels of particulate matter is reduced compared to diesel and in some situations, NOx emissions may decrease. DME has a high enough cetane number to perform well as a compression-ignition fuel but due to the poor lubrication and viscosity, it is difficult to be used as the main fuel for combustion

  10. Investigation on utilization of biogas and Karanja oil biodiesel in dual fuel mode in a single cylinder DI diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Prasanna Pattanaik, Bhabani; Nayak, Chandrakanta [Department of Mechanical Eng., Gandhi Institute for Technological Advancement, Madanpur, Bhubaneswar - 752054, Odisha (India); Kumar Nanda, Basanta [Department of Mechanical Eng., Maharaja Institute of Technology, Bhubaneswar, Odisha (India)

    2013-07-01

    In this work, experiments were performed on a single cylinder DI diesel engine by using bio-gas as a primary fuel and Karanja oil biodiesel and diesel oil as secondary fuels in dual fuel operation. The experiments were performed to measure performance parameters i.e. (brake specific fuel consumption, brake thermal efficiency and exhaust gas temperature) and emission parameters such as carbon monoxide, carbon dioxide, nitrogen oxide unburned hydro carbon and smoke etc. at different load conditions. For the dual-fuel system, the intake system of the test engine was modified to convert into biogas and biodiesel of a dual-fueled combustion engine. Biogas was injected during the intake process by gas injectors. The study showed that, the engine performance parameters like BP, BTE and EGT gradually increase with increase in engine load for all test conditions using both pilot fuels diesel and KOBD. However, the BSFC of the engine showed decreasing slope with increase in engine load for all test conditions. Above 40% engine load the BSFC values for all test fuels are very close to each other. The engine emission analysis showed that the CO2, CO and NOx emissions increase with increase in engine load for both single and dual fuel mode operation using both pilot fuels. The NOx concentration of exhaust gases in dual fuel mode is superior than that of single mode.

  11. IMPROVEMENT OF PERFORMANCE OF DUAL FUEL ENGINE OPERATED AT PART LOAD

    Directory of Open Access Journals (Sweden)

    N. Kapilan

    2010-12-01

    Full Text Available Rising petroleum prices, an increasing threat to the environment from exhaust emissions, global warming and the threat of supply instabilities has led to the choice of inedible Mahua oil (MO as one of the main alternative fuels to diesel oil in India. In the present work, MO was converted into biodiesel by transesterification using methanol and sodium hydroxide. The cost of Mahua oil biodiesel (MOB is higher than diesel. Hence liquefied petroleum gas (LPG, which is one of the cheapest gaseous fuels available in India, was fumigated along with the air to reduce the operating cost and to reduce emissions. The dual fuel engine resulted in lower efficiency and higher emissions at part load. Hence in the present work, the injection time was varied and the performance of the dual fuel engine was studied. From the engine tests, it is observed that an advanced injection time results in higher efficiency and lower emissions. Hence, advancing the injection timing is one of the ways of increasing the efficiency of LPG+MOB dual fuel engine operated at part load.

  12. Basket criticality design of a dual purpose cask for VVER 1000 spent fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Rezaeian, Mahdi [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of); Kamali, Jamshid [Atomic Energy Organization of Iran (AEOI), Tehran (Iran, Islamic Republic of)

    2016-12-15

    Dual purpose cask technology is one of the most prominent options for interim storage of spent fuels following their removal from reactors. Criticality safety of the spent fuel assemblies are ensured by design of the basket within these casks. In this study, a set of criticality design calculations of a dual purpose cask for 12 VVER 1000 spent fuel assemblies of Bushehr nuclear power plant were carried out. The basket material of borated stainless steel with 0.5 to 2.5 wt% of boron and Boral (Al-B{sub 4}C) with 1.5 to 40 wt% of boron carbide, were investigated and the minimum required receptacle pitch of the basket was determined. Using the calculated receptacle pitch of the basket, the minimum required diameter of the cavity could be established.

  13. Mechanical design issues and resolutions of a dual cooled fuel for the OPR-1000

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung-Kyu, E-mail: hkkim1@kaeri.re.kr [Innovative Nuclear Fuel Division, Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yuseong, Daejeon, 305-353 (Korea, Republic of); Kim, Jae-Yong; Yoon, Kyung-Ho [Innovative Nuclear Fuel Division, Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yuseong, Daejeon, 305-353 (Korea, Republic of)

    2011-06-15

    Highlights: > Thickness of outer cladding tube is determined by using the elastic buckling criterion. > Growth difference of the inner and outer claddings will not cause fuel rod bowing. > Structural components are designed without a drastic change of the conventional ones. - Abstract: A dual cooled fuel is recently brought into focus due to its potential of considerable power uprating. The purpose of present work is to realize the innovative concept of a dual cooled fuel to be a fuel assembly structure compatible with the OPR-1000 system. Under the framework, the critical issues such as the outer cladding thickness and the growth difference of the inner and outer cladding tubes are dealt with in this paper. We designed the thickness of outer cladding tube by using the elastic buckling criterion and safety factor analysis. From the concern of the inner cladding's bowing during irradiation, it was suggested that the outer cladding would grow more than the inner one by applying different microstructures to the inner and outer cladding tubes. It was noted that the gap between fuel rods would not be narrowed further during the different irradiation growth. The structural components such as fuel rod supporting structure, top and bottom end pieces and guide tubes could be designed without a drastic change of those of the conventional fuel. Candidate designs of the components are also presented.

  14. Stress Linearization and Strength Evaluation of the BEP's Flow Plates for a Dual Cooled Fuel Assembly

    International Nuclear Information System (INIS)

    Kim, Jae Yong; Yoon, Kyung Ho; Kang, Heung Seok; Lee, Young Ho; Lee, Kang Hee; Kim, Hyung Kyu

    2009-01-01

    A fuel assembly is composed of 5 major components, such as a top end piece (TEP), a bottom end piece (BEP), spacer grids (SGs), guide tubes (GTs) and an instrumentation tube (IT) and fuel rods (FRs). There are no ASME criteria about all components except for a TEP/BEP. The TEP/BEP should satisfy stress intensity limits in case of condition A and B of ASME, Section III, Division 1 . Subsection NB. In a dual cooled fuel assembly, the array and position of fuels are changed from those of a conventional PWR fuel assembly to achieve a power uprating. The flow plates of top/bottom end pieces (TEP/BEP) have to be modified into proper shape to provide flow holes to direct the heated coolant into/out of the fuel assembly but structural intensity of these plates within a 22.241 kN axial loading should satisfy Tresca stress limits in ASME code. In this paper, stress linearization procedure and strength evaluation of a newly designed BEP for the dual cooled fuel assembly are described

  15. Thermodynamic Analysis of Three Compressed Air Energy Storage Systems: Conventional, Adiabatic, and Hydrogen-Fueled

    Directory of Open Access Journals (Sweden)

    Hossein Safaei

    2017-07-01

    Full Text Available We present analyses of three families of compressed air energy storage (CAES systems: conventional CAES, in which the heat released during air compression is not stored and natural gas is combusted to provide heat during discharge; adiabatic CAES, in which the compression heat is stored; and CAES in which the compression heat is used to assist water electrolysis for hydrogen storage. The latter two methods involve no fossil fuel combustion. We modeled both a low-temperature and a high-temperature electrolysis process for hydrogen production. Adiabatic CAES (A-CAES with physical storage of heat is the most efficient option with an exergy efficiency of 69.5% for energy storage. The exergy efficiency of the conventional CAES system is estimated to be 54.3%. Both high-temperature and low-temperature electrolysis CAES systems result in similar exergy efficiencies (35.6% and 34.2%, partly due to low efficiency of the electrolyzer cell. CAES with high-temperature electrolysis has the highest energy storage density (7.9 kWh per m3 of air storage volume, followed by A-CAES (5.2 kWh/m3. Conventional CAES and CAES with low-temperature electrolysis have similar energy densities of 3.1 kWh/m3.

  16. 49 CFR 536.10 - Treatment of dual-fuel and alternative fuel vehicles-consistency with 49 CFR part 538.

    Science.gov (United States)

    2010-10-01

    ... vehicles-consistency with 49 CFR part 538. 536.10 Section 536.10 Transportation Other Regulations Relating... vehicles—consistency with 49 CFR part 538. (a) Statutory alternative fuel and dual-fuel vehicle fuel... economy in a particular compliance category by more than the limits set forth in 49 U.S.C. 32906(a), the...

  17. Study on using acetylene in dual fuel mode with exhaust gas recirculation

    International Nuclear Information System (INIS)

    Lakshmanan, T.; Nagarajan, G.

    2011-01-01

    Interest in employing gaseous fuels to internal combustion (IC) engines whether for stationary or mobile automotive applications has gained importance because of the economical, sustainable and environmental technical features associated with their usage. However, the incidence of preignition and knock remains a significant barrier in achieving their optimum performance potential. With the advent of latest technologies, the above barriers are eliminated. One such technique is timed manifold injection (TMI) of the gaseous fuel, which is controlled electronically to precisely monitor the induction of fuel to overcome the preignition problem in the intake. In the present investigation, acetylene was injected in the intake manifold in a single cylinder diesel engine, with a gas flow rate of 240 g/h, start of injection time is 10 o aTDC and 90 o CA (9.9 ms) duration, operated in dual fuel mode. In order to decrease the NOx emissions from acetylene-diesel engine, cooled EGR was employed. The cylinder pressure, brake thermal efficiency and emissions such as NOx, smoke, CO, HC, CO 2 and exhaust gas temperature were studied. Dual fuel operation with acetylene induction coupled with cooled EGR results in lowered NOx emissions and improved part load performance. -- Highlights: → Acetylene was tried in SI engines, but due to backfire further research was hindered as an alternative fuel. → But it is not tried in CI engine. Timed manifold injection was tried in diesel engine in the present work to combat backfire. → Author was successful in running the diesel engine in dual fuel mode. → 21% maximum diesel replacement was achieved. Author is confident that acetylene will be commercialised as a fuel for diesel engine in future.

  18. Low-Temperature Combustion of High Octane Fuels in a Gasoline Compression Ignition Engine

    Directory of Open Access Journals (Sweden)

    Khanh Duc Cung

    2017-12-01

    Full Text Available Gasoline compression ignition (GCI has been shown as one of the advanced combustion concepts that could potentially provide a pathway to achieve cleaner and more efficient combustion engines. Fuel and air in GCI are not fully premixed compared to homogeneous charge compression ignition (HCCI, which is a completely kinetic-controlled combustion system. Therefore, the combustion phasing can be controlled by the time of injection, usually postinjection in a multiple-injection scheme, to mitigate combustion noise. Gasoline usually has longer ignition delay than diesel. The autoignition quality of gasoline can be indicated by research octane number (RON. Fuels with high octane tend to have more resistance to autoignition, hence more time for fuel-air mixing. In this study, three fuels, namely, aromatic, alkylate, and E30, with similar RON value of 98 but different hydrocarbon compositions were tested in a multicylinder engine under GCI combustion mode. Considerations of exhaust gas recirculating (EGR, start of injection, and boost were investigated to study the sensitivity of dilution, local stratification, and reactivity of the charge, respectively, for each fuel. Combustion phasing (location of 50% of fuel mass burned was kept constant during the experiments. This provides similar thermodynamic conditions to study the effect of fuels on emissions. Emission characteristics at different levels of EGR and lambda were revealed for all fuels with E30 having the lowest filter smoke number and was also most sensitive to the change in dilution. Reasonably low combustion noise (<90 dB and stable combustion (coefficient of variance of indicated mean effective pressure <3% were maintained during the experiments. The second part of this article contains visualization of the combustion process obtained from endoscope imaging for each fuel at selected conditions. Soot radiation signal from GCI combustion were strong during late injection and also more intense

  19. Knock characteristics of dual-fuel combustion in diesel engines ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    system of a natural gas engine is some what different from that of the liquid fuel ... encoder. Magnetic speed sensor. Transducer. Figure 1. Illustration of system. .... Natural gas is fumigated during the induction stroke and some quantity of pilot ...

  20. Transient Temperature Distribution in a Reactor Core with Cylindrical Fuel Rods and Compressible Coolant

    Energy Technology Data Exchange (ETDEWEB)

    Vollmer, H

    1968-04-15

    Applying linearization and Laplace transformation the transient temperature distribution and weighted temperatures in fuel, canning and coolant are calculated analytically in two-dimensional cylindrical geometry for constant material properties in fuel and canning. The model to be presented includes previous models as special cases and has the following novel features: compressibility of the coolant is accounted for. The material properties of the coolant are variable. All quantities determining the temperature field are taken into account. It is shown that the solution for fuel and canning temperature may be given by the aid of 4 basic transfer functions depending on only two variables. These functions are calculated for all relevant rod geometries and material constants. The integrals involved in transfer functions determining coolant temperatures are solved for the most part generally by application of coordinate and Laplace transformation. The model was originally developed for use in steam cooled fast reactor analysis where the coolant temperature rise and compressibility are considerable. It may be applied to other fast or thermal systems after suitable simplifications.

  1. Hydrogen Fueling Station Using Thermal Compression: a techno-economic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kriha, Kenneth [Gas Technology Inst., Des Plaines, IL (United States); Petitpas, Guillaume [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Melchionda, Michael [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Soto, Herie [Shell, Houston TX (United States); Feng, Zhili [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Yanli [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-11

    The goal of this project was to demonstrate the technical and economic feasibility of using thermal compression to create the hydrogen pressure necessary to operate vehicle hydrogen fueling stations. The concept of utilizing the exergy within liquid hydrogen to build pressure rather than mechanical components such as compressors or cryogenic liquid pumps has several advantages. In theory, the compressor-less hydrogen station will have lower operating and maintenance costs because the compressors found in conventional stations require large amounts of electricity to run and are prone to mechanical breakdowns. The thermal compression station also utilizes some of the energy used to liquefy the hydrogen as work to build pressure, this is energy that in conventional stations is lost as heat to the environment.

  2. Biodiesel from plant seed oils as an alternate fuel for compression ignition engines-a review.

    Science.gov (United States)

    Vijayakumar, C; Ramesh, M; Murugesan, A; Panneerselvam, N; Subramaniam, D; Bharathiraja, M

    2016-12-01

    The modern scenario reveals that the world is facing energy crisis due to the dwindling sources of fossil fuels. Environment protection agencies are more concerned about the atmospheric pollution due to the burning of fossil fuels. Alternative fuel research is getting augmented because of the above reasons. Plant seed oils (vegetable oils) are cleaner, sustainable, and renewable. So, it can be the most suitable alternative fuel for compression ignition (CI) engines. This paper reviews the availability of different types of plant seed oils, several methods for production of biodiesel from vegetable oils, and its properties. The different types of oils considered in this review are cashew nut shell liquid (CNSL) oil, ginger oil, eucalyptus oil, rice bran oil, Calophyllum inophyllum, hazelnut oil, sesame oil, clove stem oil, sardine oil, honge oil, polanga oil, mahua oil, rubber seed oil, cotton seed oil, neem oil, jatropha oil, egunsi melon oil, shea butter, linseed oil, Mohr oil, sea lemon oil, pumpkin oil, tobacco seed oil, jojoba oil, and mustard oil. Several methods for production of biodiesel are transesterification, pre-treatment, pyrolysis, and water emulsion are discussed. The various fuel properties considered for review such as specific gravity, viscosity, calorific value, flash point, and fire point are presented. The review also portrays advantages, limitations, performance, and emission characteristics of engine using plant seed oil biodiesel are discussed. Finally, the modeling and optimization of engine for various biofuels with different input and output parameters using artificial neural network, response surface methodology, and Taguchi are included.

  3. Dual fuel operation of used transformer oil with acetylene in a DI diesel engine

    International Nuclear Information System (INIS)

    Behera, Pritinika; Murugan, S.; Nagarajan, G.

    2014-01-01

    Highlights: • Utilisation of Used transformer oil (UTO) as a fuel in a diesel engine. • UTO with acetylene in a diesel engine, on a dual fuel mode technique. • Analysis of combustion characteristics of the diesel engine. • Analysis of performance and emission characteristics of the diesel engine. - Abstract: Used transformer oil (UTO) is a waste oil obtained from power transformers and welding transformers. It possesses considerable heating value and properties similar to diesel fuel. A preliminary investigation on the utilization of the UTO in a single cylinder, four stroke small powered direct injection (DI) diesel engine revealed that at an optimum injection timing of 20°CA the engine exhibited lower nitric oxide (NO) and higher smoke emissions, compared to that of diesel operation. In order to improve the performance and reduce the smoke emission, a dual fuel operation was attempted in the present investigation. Acetylene was inducted as a primary fuel at four different flow rates viz 132 g/h, 198 g/h, 264 g/h and 330 g/h along with the air, to study the combustion, performance and emission behavior of a four-stroke, 4.4 kW diesel engine, while the UTO was injected as pilot fuel with the optimized injection timing. The experimental results were compared with diesel-acetylene dual fuel operation in the same engine. Acetylene aspiration reduced the ignition delay and maximum cylinder pressure by about 3°CA, and 25% respectively at full load in comparison with the sole UTO operation. Higher thermal efficiency and lower exhaust gas were also observed at full load. Smoke was reduced by about 13.7%, in comparison with the UTO operation at full load

  4. Conversion of diesel engines to dual fuel (propane/diesel) operations

    Energy Technology Data Exchange (ETDEWEB)

    Pepper, S W; DeMaere, D A

    1984-02-01

    A device to convert a diesel engine to dual fuel (propane/diesel) operation was developed and evaluated. Preliminary experimentation has indicated that as much as 30% of the diesel fuel consumed in diesel engines could be displaced with propane, accompanied by an improvement in fuel efficiency, engine maintenance and an overall reduction in emission levels. Dual fuel operations in both transportation and stationary applications would then project a saving of ca 90,000 barrels of diesel fuel per day by the year 1990. A turbo-charged 250 hp diesel engine was directly coupled to a dynamometer under laboratory conditions, and operated at speeds between 500 and 2500 rpm and at various torque levels. At each rpm/torque point the engine first operated on diesel fuel alone, and then increasing quantities of propane were induced into the air intake until detonation occured. Results indicate that the proportion of propane that can be safely induced into a diesel engine varies considerably with rpm and torque so that a sophisticated metering system would be required to maximize diesel oil displacement by propane. Conversion is not cost effective at 1983 price levels.

  5. Recuperative dual fuel bruner with low NO{sub x} emissions

    Energy Technology Data Exchange (ETDEWEB)

    Munko, A.; Kleine Jaeger, F.; Koehne, H. [RWTH Aachen (Germany). Energie- und Stofftransport

    2003-07-01

    In a current research project of the Arbeitsgemeinschaft Industrieller Forschungsvereinigungen e.V. (AIF) (a German research association) a new dual fuel burner for radiant tubes is being developed at the Department tof Heat and Mass Transfer (EST, RWTH Aachen University). As combustible gas (natural gas type H / Erdgas H) and fuel oil (Heizoel Extra Leicht) are used. These research activities represent the further development of the radiant tube oil burner that was developed on behalf of the AIF and in cooperation with the Forschungsgemeinschaft Industrieofenbau (FOGI e.V.) (AIF project 12345B). The radiant tube burner was designed for the furnace temperature 1000 C can the firing rate 20 to 40 kW. Due to the vaporization of the fuel oil and the homogeneous fuel mixing with a flue gas flow, at the furnace temperature 1000 C and preheated air temperature 850 C NO{sub x}-emissions below 200 mg/m{sup 3} (5% O{sub 2}, Heizoel Extra Leicht) are reached. Using gas (natural gas type H) the burner tests indicate a high NO{sub x}-reduction potential - in gas operation at a lab furnace (furnace temperature 700 C) NO{sub x}-emissions below 40 mg/m{sup 3} result. The future works within the project are the construction of a dual-fuel mixing-device for the alternative use of liquid and gaseous fuel as well as further burner operation tests at furnace temperature 1000 C. (orig.)

  6. Design of the Flow Plates for a Dual Cooled Fuel Assembly

    International Nuclear Information System (INIS)

    Kim, Jae Yong; Yoon, Kyung Ho; Lee, Young Ho; Lee, Kang Hee; Kim, Hyung Kyu

    2009-01-01

    In a dual cooled fuel assembly, the array and position of fuels are changed from those of a conventional PWR fuel assembly to achieve a power uprating. The flow plate provides flow holes to direct the heated coolant into/out of the fuel assembly and structural intensity to insure that the fuel rod is axially restrained within the spacer grids. So, flow plates of top/bottom end pieces (TEP/BEP) have to be modified into proper shape. Because the flow holes' area of a flow plate affects pressure drop, the flow holes' area must be larger than/equal to that of conventional flow plates. And design criterion of the TEP/BEP says that the flow plate should withstand a 22.241 kN axial load during handling lest a calculated stress intensity should exceed the Condition I allowable stress. In this paper, newly designed flow plates of a TEP/BEP are suggested and stress analysis is conducted to evaluate strength robustness of the flow plates for the dual cooled fuel assembly

  7. CNG (compressed natural gas) as fuel for the transport sector in Trinidad and Tobago

    Energy Technology Data Exchange (ETDEWEB)

    So`Brien, G.C.; Persad, P.; Satcunanathan, S. [University of the West Indies, St. Augustine (Trinidad)

    1996-08-01

    Several studies have established that Trinidad and Tobago is well positioned to consider the substitution of compressed natural gas (CNG) for gasoline or diesel in the transport sector. Consequently a programme of conversion of private motors was initiated. Despite considerable advertisement programs projecting CNG as an environmentally friendly and cheap fuel, there is not yet widespread acceptance of the technology. The reasons for this are analysed. It is recommended that the policy of CNG usage be reviewed and the emphasis be shifted to transport fleets. It is also recommended that tax credits be considered as an incentive to users. (author)

  8. Numerical modeling on homogeneous charge compression ignition combustion engine fueled by diesel-ethanol blends

    Directory of Open Access Journals (Sweden)

    Hanafi H.

    2016-01-01

    Full Text Available This paper investigates the performance and emission characteristics of HCCI engines fueled with oxygenated fuels (ethanol blend. A modeling study was conducted to investigate the impact of ethanol addition on the performance, combustion and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI engine fueled by diesel. One dimensional simulation was conducted using the renowned commercial software for diesel and its blend fuels with 5% (E5 and 10% ethanol (E10 (in vol. under full load condition at variable engine speed ranging from 1000 to 2750 rpm with 250 rpm increment. The model was then validated with other researcher’s experimental result. Model consists of intake and exhaust systems, cylinder, head, valves and port geometries. Performance tests were conducted for volumetric efficiency, brake engine torque, brake power, brake mean effective pressure, brake specific fuel consumption, and brake thermal efficiency, while exhaust emissions were analyzed for carbon monoxide (CO and unburned hydrocarbons (HC. The results showed that blending diesel with ethanol increases the volumetric efficiency, brake specific fuel consumption and brake thermal efficiency, while it decreases brake engine torque, brake power and brake mean effective pressure. In term of emission characteristics, the CO emissions concentrations in the engine exhaust decrease significantly with ethanol as additive. But for HC emission, its concentration increase when apply in high engine speed. In conclusion, using Ethanol as fuel additive blend with Diesel operating in HCCI shows a good result in term of performance and emission in low speed but not recommended to use in high speed engine. Ethanol-diesel blends need to researched more to make it commercially useable.

  9. Performance and emissions of a supercharged dual-fuel engine fueled by hydrogen-rich coke oven gas

    Energy Technology Data Exchange (ETDEWEB)

    Roy, M.M.; Tomita, E.; Kawahara, N.; Harada, Y.; Sakane, A. [Okayama University, Okayama (Japan). Dept. of Mechanical Engineering

    2009-12-15

    This study investigated the engine performance and emissions of a supercharged dual-fuel engine fueled by hydrogen-rich coke oven gas and ignited by a pilot amount of diesel fuel. The engine was tested for use as a cogeneration engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant pilot injection pressure and pilot quantity for different fuel-air equivalence ratios and at various injection timings without and with exhaust gas recirculation (EGR). The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. The engine was tested first without EGR condition up to the maximum possible fuel-air equivalence ratio of 0.65. A maximum indicated mean effective pressure (IMEP) of 1425 kPa and a thermal efficiency of 39% were obtained. However, the nitrogen oxides (NOx) emissions were high. A simulated EGR up to 50% was then performed to obtain lower NOx emissions. The maximum reduction of NOx was 60% or more maintaining the similar levels of IMEP and thermal efficiency. Two-stage combustion was obtained; this is an indicator of maximum power output conditions and a precursor of knocking combustion.

  10. Performance and emission characteristics of a turpentine-diesel dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Karthikeyan, R. [Adhiparasakthi Engineering College, Melmaruvathur, Tamil Nadu (India); Mahalakshmi, N.V. [I.C. Engines Division, Department of Mechanical Engineering, College of Engineering Guindy, Chennai, Tamil Nadu (India)

    2007-07-15

    This paper describes an experimental study concerning the feasibility of using bio-oil namely turpentine obtained from the resin of pine tree. The emission and performance characteristics of a D.I. diesel engine were studied through dual fuel (DF) mode. Turpentine was inducted as a primary fuel through induction manifold and diesel was admitted into the engine through conventional fueling device as an igniter. The result showed that except volumetric efficiency, all other performance and emission parameters are better than those of diesel fuel with in 75% load. The toxic gases like CO, UBHC are slightly higher than that of the diesel baseline (DBL). Around 40-45% smoke reduction is obtained with DF mode. The pollutant No{sub x} is found to be equal to that of DBL except at full load. This study has proved that approximately 75% diesel replacement with turpentine is possible by DF mode with little engine modification. (author)

  11. Characterization and effect of using Mahua oil biodiesel as fuel in compression ignition engine

    Science.gov (United States)

    Kapilan, N.; Ashok Babu, T. P.; Reddy, R. P.

    2009-12-01

    There is an increasing interest in India, to search for suitable alternative fuels that are environment friendly. This led to the choice of Mahua Oil (MO) as one of the main alternative fuels to diesel. In this investigation, Mahua Oil Biodiesel (MOB) and its blend with diesel were used as fuel in a single cylinder, direct injection and compression ignition engine. The MOB was prepared from MO by transesterification using methanol and potassium hydroxide. The fuel properties of MOB are close to the diesel and confirm to the ASTM standards. From the engine test analysis, it was observed that the MOB, B5 and B20 blend results in lower CO, HC and smoke emissions as compared to diesel. But the B5 and B20 blends results in higher efficiency as compared to MOB. Hence MOB or blends of MOB and diesel (B5 or B20) can be used as a substitute for diesel in diesel engines used in transportation as well as in the agriculture sector.

  12. Transient simulation of a catalytic converter for a dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B.; Checkel, D. [Alberta Univ., Dept. of Mechanical Enginering, Edmonton, AB (Canada); Hayes, R. E. [Alberta Univ., Department of Chemical and Material Engineering, Edmonton, AB (Canada); Zheng, M.; Mirosh, E. [Alternative Fuel Systems Inc., Calgary, AB (Canada)

    2000-06-01

    A catalytic converter of a ceramic monolith honeycomb substrate, coated with a washcoat of catalyst and attached to a natural gas/diesel dual fuel engine was simulated and studied experimentally. The paper describes the application of one-dimensional finite element model for the transient and steady state operation. Laminar flow was approximated using a dispersed plug flow model, and chemical kinetics were simulated using LHHW (Langmuir/ Hinshelwood/ Hougan/ Watson) type expressions. Simulation results were compared with experimental results for heating and cooling cycles which resulted from speed and load changes on the engine. The comparison showed a maximum difference between the two sets of emission levels of about 10 per cent, showing that the one-dimensional model is acceptable model for this dual fuel engine converter combination. 50 refs., 3 tabs., 13 figs.

  13. Investigation of TIG welding characteristics with a dual cooled rod for the fuel irradiation test

    International Nuclear Information System (INIS)

    Kim, Soo Sung; Kim, Hyung Kyu

    2008-01-01

    To establish the fabrication process, and for satisfying the requirements of the irradiation test, an TIG(Tungsten Inert Gas) welding machine for the dual cooled rods specimens was developed, and the preliminary welding experiments were performed to optimize the welding process conditions. Cladding tubes of 15.9 and 9 mm for the outer and inner diameters, respectively with a 0.57 mm thickness and end caps were used for the specimens. This paper describes the experimental results of the TIG welds and the micrograph examinations of the TIG welded specimens corresponding to various welding conditions for the dual cooled fuel irradiation test. The investigations revealed that the present TIG process satisfied the requirements for the fuel irradiation test in the HANARO research reactor

  14. Analyzing the Performance of a Dual Loop Organic Rankine Cycle System for Waste Heat Recovery of a Heavy-Duty Compressed Natural Gas Engine

    Directory of Open Access Journals (Sweden)

    Baofeng Yao

    2014-11-01

    Full Text Available A dual loop organic Rankine cycle (DORC system is designed to recover waste heat from a heavy-duty compressed natural gas engine (CNGE, and the performance of the DORC–CNGE combined system is simulated and discussed. The DORC system includes high-temperature (HT and low-temperature (LT cycles. The HT cycle recovers energy from the exhaust gas emitted by the engine, whereas the LT cycle recovers energy from intake air, engine coolant, and the HT cycle working fluid in the preheater. The mathematical model of the system is established based on the first and second laws of thermodynamics. The characteristics of waste heat energy from the CNGE are calculated according to engine test data under various operating conditions. Moreover, the performance of the DORC–CNGE combined system is simulated and analyzed using R245fa as the working fluid. Results show that the maximum net power output and the maximum thermal efficiency of the DORC system are 29.37 kW and 10.81%, respectively, under the rated power output condition of the engine. Compared with the original CNG engine, the maximum power output increase ratio and the maximum brake specific fuel consumption improvement ratio are 33.73% and 25%, respectively, in the DORC–CNGE combined system.

  15. An experimental and numerical investigation of the combustion characteristics of a dual fuel engine with a swirl chamber

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.; Karim, G.A.; Xiao, F.; Sohrabi, A. [Calgary Univ., AB (Canada). Schulich School of Engineering, Mechanical and Manufacturing Dept.

    2007-07-01

    The results of an experimental investigation of the performance of a small bore engine with a swirl chamber when operating as a dual fuel engine with commercial methane as the gaseous fuel were presented in this paper. The experiment involved using a 3-dimensional computational fluid dynamics model to predict the performance of the engine. A detailed chemical kinetics for the gaseous fuel component, consisting primarily of methane and a reduced detailed chemical kinetics for the diesel fuel while considering the turbulent combustion processes an associated performance of a dual fuel engine with a swirl chamber were incorporated in the simulation. The study experimentally and numerically investigated the effects of changes in the quantities of the liquid fuel pilot and gaseous fuels on the combustion processes, engine performance, cyclic variations, and emissions. The paper discussed the experimental approach and results. It also discussed the simulation of the dual fuel engine combustion process. It was concluded that dual fuel combustion was an effective method to burn a gaseous fuel-air mixture with a low energy density. 9 refs., 6 figs.

  16. Jatropha oil and biogas in a dual fuel CI engine for rural electrification

    Energy Technology Data Exchange (ETDEWEB)

    Luijten, C.C.M.; Kerkhof, E. [Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 6500 MB Eindhoven (Netherlands)

    2011-02-15

    This work presents the first dual fuel measurements with pure jatropha oil and biogas, using a 12 kW diesel engine generator. Reference tests are done with pure jatropha oil and with diesel to characterize the engine's thermal efficiency {eta}{sub t}, volumetric efficiency {eta}{sub v} and air-excess ratio {lambda} versus output power. An extensive parameter study is done to predict/explain the effect of dual fuel operation on {eta}{sub v} and {lambda}. Dual fuel experiments, adding different qualities (CH{sub 4}/CO{sub 2} ratios) of synthetic biogas to the intake air, show that thermal efficiency is hardly affected for higher loads. For lower loads, biogas addition results in a decrease up to 10% in thermal efficiency, independent of biogas quality. Both {eta}{sub v} and {lambda} decrease with addition of biogas, in quantitative agreement with predictions. The engine runs well up to a certain heat release fraction of methane; at higher fractions irregularities are observed, probably attributable to light end-gas knock. (author)

  17. High-Temperature, Dual-Atmosphere Corrosion of Solid-Oxide Fuel Cell Interconnects

    Science.gov (United States)

    Gannon, Paul; Amendola, Roberta

    2012-12-01

    High-temperature corrosion of ferritic stainless steel (FSS) surfaces can be accelerated and anomalous when it is simultaneously subjected to different gaseous environments, e.g., when separating fuel (hydrogen) and oxidant (air) streams, in comparison with single-atmosphere exposures, e.g., air only. This so-called "dual-atmosphere" exposure is realized in many energy-conversion systems including turbines, boilers, gasifiers, heat exchangers, and particularly in intermediate temperature (600-800°C) planar solid-oxide fuel cell (SOFC) stacks. It is generally accepted that hydrogen transport through the FSS (plate or tube) and its subsequent integration into the growing air-side surface oxide layer can promote accelerated and anomalous corrosion—relative to single-atmosphere exposure—via defect chemistry changes, such as increased cation vacancy concentrations, decreased oxygen activity, and steam formation within the growing surface oxide layers. Establishment of a continuous and dense surface oxide layer on the fuel side of the FSS can inhibit hydrogen transport and the associated effects on the air side. Minor differences in FSS composition, microstructure, and surface conditions can all have dramatic influences on dual-atmosphere corrosion behaviors. This article reviews high-temperature, dual-atmosphere corrosion phenomena and discusses implications for SOFC stacks, related applications, and future research.

  18. Jatropha oil and biogas in a dual fuel CI engine for rural electrification

    International Nuclear Information System (INIS)

    Luijten, C.C.M.; Kerkhof, E.

    2011-01-01

    This work presents the first dual fuel measurements with pure jatropha oil and biogas, using a 12 kW diesel engine generator. Reference tests are done with pure jatropha oil and with diesel to characterize the engine's thermal efficiency η t , volumetric efficiency η v and air-excess ratio λ versus output power. An extensive parameter study is done to predict/explain the effect of dual fuel operation on η v and λ. Dual fuel experiments, adding different qualities (CH 4 /CO 2 ratios) of synthetic biogas to the intake air, show that thermal efficiency is hardly affected for higher loads. For lower loads, biogas addition results in a decrease up to 10% in thermal efficiency, independent of biogas quality. Both η v and λ decrease with addition of biogas, in quantitative agreement with predictions. The engine runs well up to a certain heat release fraction of methane; at higher fractions irregularities are observed, probably attributable to light end-gas knock.

  19. Combustion and emission characteristics of a dual fuel engine operated with mahua oil and liquefied petroleum gas

    Directory of Open Access Journals (Sweden)

    Nadar Kapilan N.

    2008-01-01

    Full Text Available For the present work, a single cylinder diesel engine was modified to work in dual fuel mode. To study the feasibility of using methyl ester of mahua oil as pilot fuel, it was used as pilot fuel and liquefied petroleum gas was used as primary fuel. In dual fuel mode, pilot fuel quantity and injector opening pressure are the few variables, which affect the performance and emission of dual fuel engine. Hence, in the present work, pilot fuel quantity and injector opening pressure were varied. From the test results, it was observed that the pilot fuel quantity of 5 mg per cycle and injector opening pressure of 200 bar results in higher brake thermal efficiency. Also the exhaust emissions such as smoke, unburnt hydrocarbon and carbon monoxide are lower than other pressures and pilot fuel quantities. The higher injection pressure and proper pilot fuel quantity might have resulted in better atomization, penetration of methyl ester of mahua oil and better combustion of fuel.

  20. Dual-wavelength OR-PAM with compressed sensing for cell tracking in a 3D cell culture system

    Science.gov (United States)

    Huang, Rou-Xuan; Fu, Ying; Liu, Wang; Ma, Yu-Ting; Hsieh, Bao-Yu; Chen, Shu-Ching; Sun, Mingjian; Li, Pai-Chi

    2018-02-01

    Monitoring dynamic interactions of T cells migrating toward tumor is beneficial to understand how cancer immunotherapy works. Optical-resolution photoacoustic microscope (OR-PAM) can provide not only high spatial resolution but also deeper penetration than conventional optical microscopy. With the aid of exogenous contrast agents, the dual-wavelength OR-PAM can be applied to map the distribution of CD8+ cytotoxic T lymphocytes (CTLs) with gold nanospheres (AuNS) under 523nm laser irradiation and Hepta1-6 tumor spheres with indocyanine green (ICG) under 800nm irradiation. However, at 1K laser PRF, it takes approximately 20 minutes to obtain a full sample volume of 160 × 160 × 150 μm3 . To increase the imaging rate, we propose a random non-uniform sparse sampling mechanism to achieve fast sparse photoacoustic data acquisition. The image recovery process is formulated as a low-rank matrix recovery (LRMR) based on compressed sensing (CS) theory. We show that it could be stably recovered via nuclear-norm minimization optimization problem to maintain image quality from a significantly fewer measurement. In this study, we use the dual-wavelength OR-PAM with CS to visualize T cell trafficking in a 3D culture system with higher temporal resolution. Data acquisition time is reduced by 40% in such sample volume where sampling density is 0.5. The imaging system reveals the potential to understand the dynamic cellular process for preclinical screening of anti-cancer drugs.

  1. Feasibility Study on Dual-Cooled Annular Fuel for OPR-1000 Power Uprate

    International Nuclear Information System (INIS)

    Chun, Tae Hyun; In, Wang Kee; Oh, Dong Suck

    2010-04-01

    A dual-cooled annular fuel (DCAF) is a highly promising concept as a high power density fuel for PWR power-uprate. The purpose of this study is to assess a feasibility of 120% core power for OPR-1000 with the DCAF. So the feasibility study were done through the code establishments for annular fuel analysis, evaluations of core physics, thermal-hydraulics and safety analyses at a 120% power with OPR-1000 and the preliminary economic benefits of 20% power-uprate. As results of the analyses, DCAF at 120% power showed sufficient margins available on DNB, PCT and fuel pellet temperature relative to the solid fuel at 100% power. However, judging from an anticipated wide range of the gap conductance variation in inner and outer clearances as fuel burn-up in the reactor core, irradiation behavior of DCAF has to be observed through research reactor test. On the other hand, the nuclear physics parameters like moderator temperature coefficient, power coefficient and so on comply with the technical specifications. An impact of 20% power-uprate on NSSS and BOP was also investigated, and accordingly some components and parts need to be changed were identified. Moreover, the economical benefits from the power-uprate was roughly estimated. It turned out that the power-uprating with DCAF could give an enormous profit even considering the expenses of components and parts to be replaced, additional fuel cycle cost and extended overhaul period

  2. Autoignition of straight-run naphtha: A promising fuel for advanced compression ignition engines

    KAUST Repository

    Alabbad, Mohammed

    2017-11-24

    Naphtha, a low-octane distillate fuel, has been proposed as a promising low-cost fuel for advanced compression ignition engine technologies. Experimental and modelling studies have been conducted in this work to assess autoignition characteristics of naphtha for use in advanced engines. Ignition delay times of a certified straight-run naphtha fuel, supplied by Haltermann Solutions, were measured in a shock tube and a rapid comparison machine over wide ranges of experimental conditions (20 and 60 bar, 620–1223 K, ϕ = 0.5, 1 and 2). The Haltermann straight-run naphtha (HSRN) has research octane number (RON) of 60 and motor octane number (MON) of 58.3, with carbon range spanning C3–C9. Reactivity of HSRN was compared, via experiments and simulations, with three suitably formulated surrogates: a two-component PRF (n-heptane/iso-octane) surrogate, a three-component TPRF (toluene/n-heptane/iso-octane) surrogate, and a six-component surrogate. All surrogates reasonably captured the ignition delays of HSRN at high and intermediate temperatures. However, at low temperatures (T < 750 K), the six-component surrogate performed the best in emulating the reactivity of naphtha fuel. Temperature sensitivity and rate of production analyses revealed that the presence of cyclo-alkanes in naphtha inhibits the overall fuel reactivity. Zero-dimensional engine simulations showed that PRF is a good autoignition surrogate for naphtha at high engine loads, however, the six-component surrogate is needed to match the combustion phasing of naphtha at low engine loads.

  3. Autoignition of straight-run naphtha: A promising fuel for advanced compression ignition engines

    KAUST Repository

    Alabbad, Mohammed; Issayev, Gani; Badra, Jihad; Voice, Alexander K.; Giri, Binod; Djebbi, Khalil; Ahmed, Ahfaz; Sarathy, Mani; Farooq, Aamir

    2017-01-01

    Naphtha, a low-octane distillate fuel, has been proposed as a promising low-cost fuel for advanced compression ignition engine technologies. Experimental and modelling studies have been conducted in this work to assess autoignition characteristics of naphtha for use in advanced engines. Ignition delay times of a certified straight-run naphtha fuel, supplied by Haltermann Solutions, were measured in a shock tube and a rapid comparison machine over wide ranges of experimental conditions (20 and 60 bar, 620–1223 K, ϕ = 0.5, 1 and 2). The Haltermann straight-run naphtha (HSRN) has research octane number (RON) of 60 and motor octane number (MON) of 58.3, with carbon range spanning C3–C9. Reactivity of HSRN was compared, via experiments and simulations, with three suitably formulated surrogates: a two-component PRF (n-heptane/iso-octane) surrogate, a three-component TPRF (toluene/n-heptane/iso-octane) surrogate, and a six-component surrogate. All surrogates reasonably captured the ignition delays of HSRN at high and intermediate temperatures. However, at low temperatures (T < 750 K), the six-component surrogate performed the best in emulating the reactivity of naphtha fuel. Temperature sensitivity and rate of production analyses revealed that the presence of cyclo-alkanes in naphtha inhibits the overall fuel reactivity. Zero-dimensional engine simulations showed that PRF is a good autoignition surrogate for naphtha at high engine loads, however, the six-component surrogate is needed to match the combustion phasing of naphtha at low engine loads.

  4. The Effect of Inhomogeneous Compression on Water Transport in the Cathode of a Proton Exchange Membrane Fuel Cell

    DEFF Research Database (Denmark)

    Olesen, Anders Christian; Berning, Torsten; Kær, Søren Knudsen

    2012-01-01

    A three-dimensional, multicomponent, two-fluid model developed in the commercial CFD package CFX 13 (ANSYS Inc.) is used to investigate the effect of porous media compression on water transport in a proton exchange membrane fuel cell (PEMFC). The PEMFC model only consist of the cathode channel, gas....... Furthermore, the presence of irreducible liquid water is taken into account. In order to account for compression, porous media morphology variations are specified based on the gas diffusion layer (GDL) through-plane strain and intrusion which are stated as a function of compression. These morphology...... variations affect gas and liquid water transport, and hence liquid water distribution and the risk of blocking active sites. Hence, water transport is studied under GDL compression in order to investigate the qualitative effects. Two simulation cases are compared; one with and one without compression....

  5. A Study on the Structural Integrity Issues of a Dual-Cooled Fuel Rod

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung-Kyu; Lee, Kang-Hee; Lee, Young-Ho; Yoon, Kyung-Ho; Kim, Jae-Yong; Song, Kun-Woo [Korea Atomic Energy Research Institute, 1045 Daedeokdaero Yuseong Daejeon 305-353 (Korea, Republic of)

    2009-06-15

    A dual-cooled fuel rod has an internal coolant flow passage in addition to the external one. A remarkable power up-rate can be achieved due to the increased surface area, which may draw great interests from the fuel researchers, designers and vendors. However, it requires effective resolution to the difficult technical issues when a fuel assembly is to be realized. It becomes much more difficult if a tough boundary condition needs to be satisfied such as a compatibility with the existing reactor internal structures. This kind of challenge is tackled through a national R and D project in Korea: to develop the structural components of a dual-cooled fuel that should be compatible with the current OPR 1000 (Korea Standard Nuclear Power Plant) internal structures. Fuel rod supporting structures, top and bottom end pieces and guide tubes are the components. Besides, the fuel rod components have to be developed as well since the fuel rod's geometry becomes much different from the conventional rod's one. The dimension change may well affect the above mentioned structural components. As a part of the work, structural integrity of the components of a dual-cooled fuel rod is studied in this paper. The investigated topics are: i) the thickness determination of a cladding tube (especially outer tube of a large diameter), ii) vibration issue of an inner cladding tube, iii) design concern of plenum spring and spacer. The cladding thickness issue arises due to the increased outside diameter of a fuel rod, which is caused by an internal flow passage formation. Among the criteria for the thickness determination, an elastic buckling criteria was focused on. Theoretical background for the well-known formula (such as a stability problem) was revisited. Verification tests were carried out independently with using a cladding tube of PHWR fuel rod. Results showed that the formula was not conservative to apply for the cladding thickness determination. Minimum thickness for the

  6. The flow behavior and constitutive equation in isothermal compression of FGH4096-GH4133B dual alloy

    International Nuclear Information System (INIS)

    Liu, Yanhui; Yao, Zekun; Ning, Yongquan; Nan, Yang; Guo, Hongzhen; Qin, Chun; Shi, Zhifeng

    2014-01-01

    Highlights: • Hot compression behaviors of the FGH4096-GH4133B dual alloy were investigated. • Constitutive equation also represented deformation behavior of a dual alloy. • The effects of deformation activation energy on the microstructures were discussed. • Constitutive equation represented an accurate and precise estimate of flow stress. - Abstract: The electron beam welding of superalloy FGH4096 and GH4133B was conducted, and the cylindrical compression specimens were machined from the central part of the electron beam weldments. Isothermal compression tests were carried out on electron beam weldments FGH4096-GH4133B alloy at the temperatures of 1020–11140 °C (the nominal γ′-transus temperature is about 1080 °C) and the strain rates of 0.001–1.0 s −1 with the height reduction of 50%. True stress–true strain curves are sensitive to the deformation temperature and strain rate, and the flow stress decreases with the increasing deformation temperature and the decreasing strain rate. The true stress–true strain curves can indicate the intrinsic relationship between the flow stress and the thermal-dynamic behavior. The apparent activation energy of deformation at the strain of 0.6 was calculated to be 550 kJ/mol, and the apparent activation energy has a great effect on the microstructure. The constitutive equation that describes the flow stress as a function of strain rate and deformation temperature was proposed for modeling the hot deformation process of FGH4096-GH4133B electron beam weldments. The constitutive equation at the strain of 0.6 was established using the hyperbolic law. The relationship between the strain and the values of parameters was studied, and the cubic functions were built. The constitutive equation during the whole process can be obtained based on the parameters under different strains. Comparing the experimental flow stress and the calculated flow stress, the constitutive equation obtained in this paper can be very good

  7. Simulation of Cycle-to-Cycle Variation in Dual-Fuel Engines

    KAUST Repository

    Jaasim, Mohammed

    2017-03-13

    Standard practices of internal combustion (IC) engine experiments are to conduct the measurements of quantities averaged over a large number of cycles. Depending on the operating conditions, the cycle-to-cycle variation (CCV) of quantities, such as the indicated mean effective pressure (IMEP) are observed at different levels. Accurate prediction of CCV in IC engines is an important but challenging task. Computational fluid dynamics (CFD) simulations using high performance computing (HPC) can be used effectively to visualize such 3D spatial distributions. In the present study, a dual fuel large engine is considered, with natural gas injected into the manifold accompanied with direct injection of diesel pilot fuel to trigger ignition. Multiple engine cycles in 3D are simulated in series as in the experiments to investigate the potential of HPC based high fidelity simulations to accurately capture the cycle to cycle variation in dual fuel engines. Open cycle simulations are conducted to predict the combined effect of the stratification of fuel-air mixture, temperature and turbulence on the CCV of pressure. The predicted coefficient of variation (COV) of pressure compared to the results from closed cycle simulations and the experiments.

  8. Theoretical and experimental investigations on the performance of dual fuel diesel engine with hydrogen and LPG as secondary fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lata, D.B.; Misra, Ashok [Department of Mechanical Engineering, Birla Institute of Technology, Mesra, Ranchi 835215 (India)

    2010-11-15

    The mathematical models to predict pressure, net heat release rate, mean gas temperature, and brake thermal efficiency for dual fuel diesel engine operated on hydrogen, LPG and mixture of LPG and hydrogen as secondary fuels are developed. In these models emphasis have been given on spray mixing characteristics, flame propagation, equilibrium combustion products and in-cylinder processes, which were computed using empirical equations and compared with experimental results. This combustion model predicts results which are in close agreement with the results of experiments conducted on a multi cylinder turbocharged, intercooled gen-set diesel engine. The predictions are also in close agreement with the results on single cylinder diesel engine obtained by other researchers. A reasonable agreement between the predicted and experimental results reveals that the presented model gives quantitatively and qualitatively realistic prediction of in-cylinder processes and engine performances during combustion. (author)

  9. Dual Pressure versus Hybrid Recuperation in an Integrated Solid Oxide Fuel Cell Cycle – Steam Cycle

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2014-01-01

    A SOFC (solid oxide fuel cell) cycle running on natural gas was integrated with a ST (steam turbine) cycle. The fuel is desulfurized and pre-reformed before entering the SOFC. A burner was used to combust the remaining fuel after the SOFC stacks. The off-gases from the burner were used to produce...... pressure configuration steam cycle combined with SOFC cycle (SOFC-ST) was new and has not been studied previously. In each of the configuration, a hybrid recuperator was used to recovery the remaining energy of the off-gases after the HRSG. Thus, four different plants system setups were compared to each...... other to reveal the most superior concept with respect to plant efficiency and power. It was found that in order to increase the plant efficiency considerably, it was enough to use a single pressure with a hybrid recuperator instead of a dual pressure Rankine cycle....

  10. Effect of Variable Compression Ratio on Performance of a Diesel Engine Fueled with Karanja Biodiesel and its Blends

    Science.gov (United States)

    Mishra, Rahul Kumar; soota, Tarun, Dr.; singh, Ranjeet

    2017-08-01

    Rapid exploration and lavish consumption of underground petroleum resources have led to the scarcity of underground fossil fuels moreover the toxic emissions from such fuels are pernicious which have increased the health hazards around the world. So the aim was to find an alternative fuel which would meet the requirements of petroleum or fossil fuels. Biodiesel is a clean, renewable and bio-degradable fuel having several advantages, one of the most important of which is being its eco-friendly and better knocking characteristics than diesel fuel. In this work the performance of Karanja oil was analyzed on a four stroke, single cylinder, water cooled, variable compression ratio diesel engine. The fuel used was 5% - 25% karanja oil methyl ester by volume in diesel. The results such obtained are compared with standard diesel fuel. Several properties i.e. Brake Thermal Efficiency, Brake Specific Fuel Consumptions, Exhaust Gas Temperature are determined at all operating conditions & at variable compression ratio 17 and 17.5.

  11. Performance and emission comparison of a supercharged dual-fuel engine fueled by producer gases with varying hydrogen content

    Energy Technology Data Exchange (ETDEWEB)

    Mohon Roy, Murari [Rajshahi University of Engineering and Technology (JSPS Research Fellow, Okayama University), Tsushima-Naka 3, Okayama 700-8530 (Japan); Department of Mechanical Engineering, Okayama University, Tsushima-Naka 3, Okayama 700-8530 (Japan); Tomita, Eiji; Kawahara, Nobuyuki; Harada, Yuji [Department of Mechanical Engineering, Okayama University, Tsushima-Naka 3, Okayama 700-8530 (Japan); Sakane, Atsushi (Mitsui Engineering and Shipbuilding Co. Ltd., 6-4 Tsukiji 5-chome, Chuo-ku, Tokyo)

    2009-09-15

    This study investigated the effect of hydrogen content in producer gas on the performance and exhaust emissions of a supercharged producer gas-diesel dual-fuel engine. Two types of producer gases were used in this study, one with low hydrogen content (H{sub 2} = 13.7%) and the other with high hydrogen content (H{sub 2} = 20%). The engine was tested for use as a co-generation engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant injection pressure and injection quantity for different fuel-air equivalence ratios and at various injection timings. The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. Two-stage combustion was obtained; this is an indicator of maximum power output conditions and a precursor of knocking combustion. Better combustion, engine performance, and exhaust emissions (except NO{sub x}) were obtained with the high H{sub 2}-content producer gas than with the low H{sub 2}-content producer gas, especially under leaner conditions. Moreover, a broader window of fuel-air equivalence ratio was found with highest thermal efficiencies for the high H{sub 2}-content producer gas. (author)

  12. Impedance study of membrane dehydration and compression in proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Le Canut, Jean-Marc; Latham, Ruth; Merida, Walter; Harrington, David A. [Institute for Integrated Energy Systems, University of Victoria, Victoria, British Columbia (Canada)

    2009-07-15

    Electrochemical impedance spectroscopy (EIS) is used to measure drying and rehydration in proton exchange membrane fuel cells running under load. The hysteresis between forward and backward acquisition of polarization curves is shown to be largely due to changes in the membrane resistance. Drying tests are carried out with hydrogen and simulated reformate (hydrogen and carbon dioxide), and quasi-periodic drying and rehydration conditions are studied. The membrane hydration state is clearly linked to the high-frequency arc in the impedance spectrum, which increases in size for dry conditions indicating an increase in membrane resistance. Changes in impedance spectra as external compression is applied to the cell assembly show that EIS can separate membrane and interfacial effects, and that changes in membrane resistance dominate. Reasons for the presence of a capacitance in parallel with the membrane resistance are discussed. (author)

  13. The evaluation of minimum cooling period for loading of PWR spent nuclear fuel of a dual purpose metal cask

    Energy Technology Data Exchange (ETDEWEB)

    Dho, Ho Seog; Kim, Tae Man; Cho, Chun Hyung [Korea Radioactive Waste Agency, Daejeon (Korea, Republic of)

    2016-12-15

    Recently, because the wet pool storage facilities of NPPs in Korea has become saturated, there has been much active R and D on an interim dry storage system using a transportation and storage cask. Generally, the shielding evaluation for the design of a spent fuel transportation and storage cask is performed by the design basis fuel, which selects the most conservative fuel among the fuels to be loaded into the cask. However, the loading of actual spent fuel into the transportation metal cask is not limited to the design basis fuel used in the shielding evaluation; the loading feasibility of actual spent fuel is determined by the shielding evaluation that considers the characteristics of the initial enrichment, the maximum burnup and the minimum cooling period. This study describes a shielding analysis method for determining the minimum cooling period of spent fuel that meets the domestic transportation standard of the dual purpose metal cask. In particular, the spent fuel of 3.0-4.5wt% initial enrichment, which has a large amount of release, was evaluated by segmented shielding calculations for efficient improvement of the results. The shielding evaluation revealed that about 81% of generated spent fuel from the domestic nuclear power plants until 2008 could be transported by the dual purpose metal cask. The results of this study will be helpful in establishing a technical basis for developing operating procedures for transportation of the dual purpose metal cask.

  14. The evaluation of minimum cooling period for loading of PWR spent nuclear fuel of a dual purpose metal cask

    International Nuclear Information System (INIS)

    Dho, Ho Seog; Kim, Tae Man; Cho, Chun Hyung

    2016-01-01

    Recently, because the wet pool storage facilities of NPPs in Korea has become saturated, there has been much active R and D on an interim dry storage system using a transportation and storage cask. Generally, the shielding evaluation for the design of a spent fuel transportation and storage cask is performed by the design basis fuel, which selects the most conservative fuel among the fuels to be loaded into the cask. However, the loading of actual spent fuel into the transportation metal cask is not limited to the design basis fuel used in the shielding evaluation; the loading feasibility of actual spent fuel is determined by the shielding evaluation that considers the characteristics of the initial enrichment, the maximum burnup and the minimum cooling period. This study describes a shielding analysis method for determining the minimum cooling period of spent fuel that meets the domestic transportation standard of the dual purpose metal cask. In particular, the spent fuel of 3.0-4.5wt% initial enrichment, which has a large amount of release, was evaluated by segmented shielding calculations for efficient improvement of the results. The shielding evaluation revealed that about 81% of generated spent fuel from the domestic nuclear power plants until 2008 could be transported by the dual purpose metal cask. The results of this study will be helpful in establishing a technical basis for developing operating procedures for transportation of the dual purpose metal cask

  15. Combustion performance, flame, and soot characteristics of gasoline–diesel pre-blended fuel in an optical compression-ignition engine

    International Nuclear Information System (INIS)

    Jeon, Joonho; Lee, Jong Tae; Kwon, Sang Il; Park, Sungwook

    2016-01-01

    Highlights: • Gasoline–diesel pre-blended fuel was investigated in an optical direct-injection diesel engine. • KIVA3V-CHEMKIN code modeled blended fuel spray and combustion with discrete multi-component model. • Flame and soot characteristics in the combustion chamber were shown by optical kits. • Combustion performance and soot emissions for gasoline–diesel blended fuel were discussed. - Abstract: Among the new combustion technologies available for internal combustion engines to enhance performance and reduce exhausted emissions, the homogeneous charge compression ignition method is one of the most effective strategies for the compression-ignition engine. There are some challenges to realize the homogeneous charge compression ignition method in the compression-ignition engine. The use of gasoline–diesel blended fuel has been suggested as an alternative strategy to take advantages of homogeneous charge compression ignition while overcoming its challenges. Gasoline and diesel fuels are reference fuels for the spark-ignition and compression-ignition engines, respectively, both of which are widely used. The application of both these fuels together in the compression-ignition engine has been investigated using a hybrid injection system combining port fuel injection (gasoline) and direct injection (diesel); this strategy is termed reactivity controlled compression ignition. However, the pre-blending of gasoline and diesel fuels for direct injection systems has been rarely studied. For the case of direct injection of pre-blended fuel into the cylinder, various aspects of blended fuels should be investigated, including their spray breakup, fuel/air mixing, combustion development, and emissions. In the present study, the use of gasoline–diesel pre-blended fuel in an optical single-cylinder compression-ignition engine was investigated under various conditions of injection timing and pressure. Furthermore, KIVA-3V release 2 code was employed to model the

  16. STUDY OF ALTERNATIVE FUELS AND EFFECTS OF COMPRESSION RATIO ON THERMAL EFFICIENCY AND ENGINE POWER

    Directory of Open Access Journals (Sweden)

    Sarjito Sarjito

    2017-01-01

    Full Text Available This paper was a case study during the sabatical program at Kingston University London in February 2007. It has been studied by team of motorsport automotive department Kingston University London and it has been elaborated as a final project on Master Program. This study takes into account some of the issues surrounding the debate about alcohol fuels in Motorsport and the wider automotive sector and is primarily concerned to add data where there seems to be little existing research since Motorsport is a secretive business. Motorsport plays an important part in the automotive industry and is a sport enjoyed worldwide. Racing practice is regarded as using the best available resources and technology as it requires optimal performance. The racing arena gives engineers the opportunity to test valuable technological solutions to prove their merits. Therefore, racing is the natural starting point for introducing new technological solutions to the public and could lead to the wholesale conversion to renewable fuels to meet our automotive energy needs. Alcohol has unique properties that make superior in many ways to ordinary gasoline. The higher knock resistance allows for higher compression ratios to be utilized resulting in higher power outputs and thermal efficiency. The efficient use of energy is of growing concern in all spheres of life and the automotive sector needs to be front runner in these efforts.

  17. Mechanical Performance Evaluation of a Top End Piece for Dual Cooled Fuels

    International Nuclear Information System (INIS)

    Kim, Jae Yong; Yoon, Kyung Ho; Kim, Hyung Kyu; Choi, Woo Seok

    2011-01-01

    A fuel assembly consists of five major components, i.e., a top end piece (TEP), a bottom end piece (BEP), spacer grids (SGs), guide tubes (GTs) and an instrumentation tube (IT): in addition, it also includes fuel rods (FRs). The TEP/BEP should satisfy stress intensity limits according to the conditions A and B of ASME, Section III, Division 1.Subsection NB. In a dual-cooled fuel assembly, the array and position of fuel rods are different from those in a conventional PWR fuel assembly; these changes are necessary for achieving power uprating. The flow plates of the TEP and BEP have to be modified accordingly. The pattern and shape of the flow holes were newly designed. To verify the strength compatibility, the Tresca stress limit according to the ASME code was investigated in the case of an axial load of 22.241 kN. In this paper, the stress linearization procedure for strength evaluation of a newly designed TEP is presented

  18. Optimization experiment of gas oil direct injection valve for CNG dual fuel diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B.Y. [Chonnam National University Graduate School, Jeonju (Korea); Park, C. K. [Chonnam National University, Jeonju (Korea)

    1999-04-01

    In this study, we studied for a conversion from diesel engine to natural gas dual fuel engine. For this experimental, we tested about the injection quantity characteristics of pilot valve with the plunger diameter at the retraction volume and investigated to the engine performance and exhaust emissions with the nozzle hole number and injection nozzle diameter. As a result, when the plunger diameter is 7.5 mm at the retraction volume, 25 mm{sup 3}/st, the injection quantity characteristics develop. Also, when a nozzle type is 4*{phi} 0.24, total hydrocarbon(THC) emission reduce at low equivalence ratio. (author). 5 refs., 10 figs., 2 tabs.

  19. Investigation on the performance and emission parameters of dual fuel diesel engine with mixture combination of hydrogen and producer gas as secondary fuel

    Directory of Open Access Journals (Sweden)

    A. E. Dhole

    2016-06-01

    Full Text Available This study presents experimental investigation in to the effects of using mixture of producer gas and hydrogen in five different proportions as a secondary fuel with diesel as pilot fuel at wide range of load conditions in dual fuel operation of a 4 cylinder turbocharged and intercooled 62.5 kW gen-set diesel engine at constant speed of 1500 RPM. Secondary fuel Substitution is in different percentage of diesel at each load. To generate producer gas, the rice husk was used as source in the downdraft gasifier. The performance and emission characteristics of the dual fuel engine are compared with that of diesel engine at different load conditions. It was found that of all the combinations tested, mixture combination of PG:H2=(60:40% is the most suited one at which the brake thermal efficiency is in good comparison to that of diesel operation. Decreased NOx emissions and increased CO emissions were observed for dual fuel mode for all the fuel combinations compared to diesel fuel operation.

  20. Evaluation of bundle duct interaction by out-of-pile compression test of FBR fuel pin bundles

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Kosuke; Yamamoto, Yuji; Nagamine, Tsuyoshi; Maeda, Koji [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center

    2001-06-01

    Bundle duct interaction (BDI) caused by expansion of fuel pin bundle is a main factor to limit the fuel lifetime. Therefore, it is important for the design of fast reactor fuel assembly to understand the fuel pin deformation behavior under BDI condition. In order to understand the fuel pin deformation behavior under BDI condition, out-of-pile compression tests were conducted for FBR fuel pin bundle by use of X-ray CT equipment. In these compression tests, two kinds of fuel pin bundles were conducted. One was the fuel pin bundle with the short wire-pitch and the other was the fuel pin bundle with the short wire-pitch and large diameter claddings. The general discussions were also performed based on the results of out-of-pile compression tests obtained by use of X-ray CT equipment in the previous work. Following results were obtained. 1) The occurrence of the pin-to-duct contact depends on the wire-pitch. In the fuel pin bundle with large wire-pitch, the pin-to-duct contact occurred at the early stage of BDI. The reason of this result is due to the low bowing rigidity of the fuel pins with long wire-pitch. 2) The value of the ovalation stiffness strongly depends on the geometry of cladding (diameter, thickness) and especially on wire-pitch. This result in this work revealed that the occurrence of the pin-to-duct contact depends on the value of the ovalation stiffness. 3) The occurrence of wire dispersion and dispersive displacement of pins depends on the wire-pitch strongly. In the fuel pin bundle with the long wire-pitch, the occurrence of the above-mentioned suppression mechanism to BDI is remarkable. 4) The suppression mechanism to BDI of the fuel pin bundle with the long wire-pitch is elastic oval deformation of cladding, wire dispersion and dispersive displacement of pins. On the other hand, the elastic and plastic oval deformation of cladding is the major suppression mechanism to BDI in the fuel pin bundle with the short wire-pitch. 5) The appearance of

  1. Effects of pilot injection pressure on the combustion and emissions characteristics in a diesel engine using biodiesel–CNG dual fuel

    International Nuclear Information System (INIS)

    Ryu, Kyunghyun

    2013-01-01

    Highlights: • Injection pressure of pilot fuel in dual fuel combustion (DFC) affects the engine power and exhaust emissions. • In the biodiesel–CNG DFC mode, the combustion begins and ends earlier as the pilot-fuel injection pressure increases. • The ignition delay in the DFC mode is about 1.2–2.6 °CA longer than that in the diesel single fuel combustion (SFC) mode. • The smoke and NOx emissions are significantly reduced in the DFC mode. - Abstract: Biodiesel–compressed natural gas (CNG) dual fuel combustion (DFC) system is studied for the simultaneous reduction of particulate matters (PM) and nitrogen oxides (NOx) from diesel engine. In this study, biodiesel is used as a pilot injection fuel to ignite the main fuel, CNG of DFC system. In particular, the pilot injection pressure is controlled to investigate the characteristics of engine performance and exhaust emissions in a single cylinder diesel engine. The results show that the indicated mean effective pressure (IMEP) of biodiesel–CNG DFC mode is lower than that of diesel single fuel combustion (SFC) mode at higher injection pressure. However, the combustion stability of biodiesel–CNG DFC mode is increased with the increase of pilot injection pressure. At the same injection pressure, the start of combustion of biodiesel–CNG DFC is delayed compared to diesel SFC due to the increase of ignition delay of pilot fuel. On the contrary, it is observed that as the pilot injection pressure increase, the combustion process begins and ends a little earlier for biodiesel–CNG DFC. The ignition delay in the DFC is about 1.2–2.6 °CA longer compared to diesel SFC, but decreases with increases of pilot injection pressure. Smoke and NOx emissions are decreased and increased, respectively, as the pilot injection pressure increases in the biodiesel–CNG DFC. In comparison to diesel SFC, smoke emissions are significantly reduced over all the operating conditions and NOx emissions also exhibited similar

  2. Investigation of GDL compression effects on the performance of a PEM fuel cell cathode by lattice Boltzmann method

    Science.gov (United States)

    Molaeimanesh, G. R.; Nazemian, M.

    2017-08-01

    Proton exchange membrane (PEM) fuel cells with a great potential for application in vehicle propulsion systems will have a promising future. However, to overcome the exiting challenges against their wider commercialization further fundamental research is inevitable. The effects of gas diffusion layer (GDL) compression on the performance of a PEM fuel cell is not well-recognized; especially, via pore-scale simulation technique capturing the fibrous microstructure of the GDL. In the current investigation, a stochastic microstructure reconstruction method is proposed which can capture GDL microstructure changes by compression. Afterwards, lattice Boltzmann pore-scale simulation technique is adopted to simulate the reactive gas flow through 10 different cathode electrodes with dissimilar carbon paper GDLs produced from five different compression levels and two different carbon fiber diameters. The distributions of oxygen mole fraction, water vapor mole fraction and current density for the simulated cases are presented and analyzed. The results of simulations demonstrate that when the fiber diameter is 9 μm adding compression leads to lower average current density while when the fiber diameter is 7 μm the compression effect is not monotonic.

  3. Dual winch nuclear fuel transfer system providing more reliable fuel transfer during refueling operations

    International Nuclear Information System (INIS)

    Meuschke, R.E.; Harper, M.J.; Stefko, D.J.

    1991-01-01

    This paper describes a nuclear power plant having an auxiliary building, a containment building having the wall, a track extending through a transfer tube within the containment wall, and a fuel transfer system for moving fuel assemblies along the track between the auxiliary building side and the containment building side of the containment wall. It comprises: a car having wheels for movement along spaced rails of the track and further having a carrying basket for one or more fuel assemblies; winch means located on the auxiliary building side of the containment wall and above the water level existing over the track during refueling operations to drive the car along the track; first cable means and second cable means extending substantially vertically downward from the winch means to the tack level; first sheave means for directing the first and the second cable means substantially in the horizontal direction along the track; means for securing the first cable means to the car so that winch pulling force on the first cable means drives the car away from the containment building; second sheave means located near the containment end of the transfer tube

  4. Performance and emissions of a heavy-duty diesel/LPG dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Schaberg, Paul [Sasol Technology, Cape Town (South Africa)

    2013-06-01

    This paper describes an investigation into the combustion characteristics and exhaust emissions of a heavy-duty truck engine which has been equipped with an aftermarket conversion kit to enable operation as a diesel/LPG (Liquefied Petroleum Gas) dual fuel engine. During operation diesel fuel is displaced by LPG which is vaporised and metered into the inlet manifold by means of solenoid injectors. It was found that, as the LPG fuelling rate is increased, the cylinder pressure rise rates and peak cylinder pressures increase, as do the carbon monoxide and unburned hydrocarbon emissions. At higher loads it was found that the LPG autoignites independently of the diesel fuel, resulting in very high rates of cylinder pressure rise. Particulate and nitrogen oxide emissions remain largely unchanged, and carbon dioxide emissions are reduced due to the lower carbon content of the LPG fuel. Different LPG compositions were also investigated and it was found that the LPG properties that have the most significant effect on combustion and emissions were the autoignition and volatility characteristics. (orig.)

  5. Assessment of Gap Conductance Impact on Heat Split in Dual Cooled Annular Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kun Ho; Chun, Tae Hyun; In, Wang Kee; Yang, Yong Sik; Song, Kun Woo

    2007-07-15

    As a next generation fuel for PWR, a dual cooling annular fuel is being considered promisingly due to various advantage. It is able to increase the thermal margin significantly from not only large heat transfer area but also thin fuel pellet thickness. But the thermal margin at nominal condition could be degraded at certain burnup range because of the inappropriate heat split to inner and outer flow channels. A key factor to influence the heat split is the gap conductances in inner and outer clearances, which varies in terms of thermal expansion, swelling, creep, and so on in the cladding and pellet. As results of the investigation, particularly in the case of low gap conductance when the fuel rod burnup is relatively high, there is high probability that design targets might be violated. Therefore some effort is inevitable to address the concern. But, in parallel, it is necessary to more in detail investigate whether the assumed gap conductance for this analysis and the present design targets are reasonable through further reviews.

  6. ISO New England Dual Fuel Capabilities to Limit Natural Gas and Electricity Interdependencies

    Energy Technology Data Exchange (ETDEWEB)

    Adder, Justin M. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)

    2016-04-22

    Since 2000, natural gas has seen tremendous growth as a fuel source for electricity generation in the United States (U.S.) with annual installations exceeding 20 GW in all but four years. It also accounts for an increasingly significant share of the nation’s electricity generation, growing from around 15 percent in the early part of the 2000s to between 26 and 29 percent in the last three years. (1) Increasing reliance on natural gas has led to concerns that an extreme weather event – which may cause curtailments in gas delivery – or a natural gas infrastructure failure could lead to local or regional electric reliability issues. (2) These concerns stem from differences in delivery methods of natural gas to electric generating units (EGUs) contrasted with the fuel delivery and storage methods for traditional baseload power systems (i.e. coal and nuclear units).1 (3) Although it seems that there is an abundance of natural gas in a post-shale gas world, infrastructure limitations and differences in electric and natural gas markets persist that differentiate natural gas-fired generators from traditional baseload power generators. Such concerns can be partially mitigated by modifying natural gas EGUs for operation on secondary fuels and installing on-site fuel storage for the secondary fuel, thus ensuring continuity of operation in the case of a gas delivery problem.2 This report examines technical, regulatory, and market issues associated with operating power plants primarily fueled with natural gas, on a secondary fuel, such as fuel oil or liquefied natural gas (LNG). In addition, a regional case study was completed to identify the current and near-term potential for dual fuel operation in New England, along with a market impact analysis of potential cost savings during an extreme weather event. The New England Independent System Operator (ISO-NE) was selected as the study area based on a preponderance of natural gas-fired generators contributing to the

  7. Combustion and emissions control in diesel-methane dual fuel engines: The effects of methane supply method combined with variable in-cylinder charge bulk motion

    International Nuclear Information System (INIS)

    Carlucci, Antonio P.; Laforgia, Domenico; Saracino, Roberto; Toto, Giuseppe

    2011-01-01

    Highlights: → We studied dual fuel combustion in diesel engines. → Bulk flow structure of in-cylinder charge and methane supply method were investigated. → Swirl charge motion is capable to enhance air-methane mixture oxidation at low loads. → Methane port injection is capable to reduce unburned hydrocarbons and nitric oxides. - Abstract: In this paper, the results of an extensive experimental campaign about dual fuel combustion development and the related pollutant emissions are reported, paying particular attention to the effect of both the in-cylinder charge bulk motion and methane supply method. A diesel common rail research engine was converted to operate in dual fuel mode and, by activating/deactivating the two different inlet valves of the engine (i.e. swirl and tumble), three different bulk flow structures of the charge were induced inside the cylinder. A methane port injection method was proposed, in which the gaseous fuel was injected into the inlet duct very close to the intake valves, in order to obtain a stratified-like air-fuel mixture up to the end of the compression stroke. For comparison purposes, a homogeneous-like air-fuel mixture was obtained injecting methane more upstream the intake line. Combining the different positions of the methane injector and the three possible bulk flow structures, seven different engine inlet setup were tested. In this way, it was possible to evaluate the effects on dual fuel combustion due to the interaction between methane injector position and charge bulk motion. In addition, methane injection pressure and diesel pilot injection parameters were varied setting the engine at two operating conditions. For some interesting low load tests, the combustion development was studied more in detail by means of direct observation of the process, using an in-cylinder endoscope and a digital CCD camera. Each combustion image was post-processed by a dedicated software, in order to extract only those portions with flame

  8. Combustion of simulated biogas in a dual-fuel diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Henham, A.; Makkar, M.K. [University of Surrey, Guildford (United Kingdom). School of Mechanical and Materials Engineering

    1998-12-31

    Technology related to biogas has been steadily developed over the last 50 years from small individually designed units to larger production plants. The development, however, has largely taken place on the side of biogas production and anaerobic waste treatment. Utilization of the gas produced by these methods has only recently been the subject of more scientific evaluation. The transformation of energy through biogas into the thermodynamically higher valued mechanical energy successfully and economically is now the most important research area in this field. Of the engine work already published, most concerns spark-ignited engines. The authors` research work concerns the use of biogas in dual-fuel diesel engines. It examines engine performance using simulated biogas of varying quality representing the range of methane:carbon dioxide composition which may be encountered in gas from different sources. The total programme includes the effects of biogas quality and of the proportion of energy from pilot fuel injection over a range of speeds and loads, investigations into the performance parameters over a range of compositions of gaseous mixture. A two-cylinder, indirect-injection diesel engine of stationary type is being used as the first experimental test bed in this work and the variation of quality is provided by mixing natural gas and carbon dioxide. A data acquisition system for an in-cylinder pressure and crank angle is being used successfully and some emissions measurements are also available, particularly for CO and O{sub 2}. The nature of combustion process in the dual-fuel engine is examined through pressure-crank angle data and studies of characteristics affecting engine efficiency. (author)

  9. Diesel vs. compressed natural gas for school buses: a cost-effectiveness evaluation of alternative fuels

    International Nuclear Information System (INIS)

    Cohen, J.T.

    2005-01-01

    Reducing emissions from school buses is a priority for both state and federal regulators. Two popular alternative technologies to conventional diesel (CD) are emission controlled diesel (ECD), defined here to be diesel buses equipped with continuously regenerating particle filters, and engines fueled by compressed natural gas (CNG). This paper uses a previously published model to quantify the impact of particulate matter (PM), oxides of nitrogen (NO x ), and sulfur dioxide (SO 2 ) emissions on population exposure to ozone and to primary and secondary PM, and to quantify the resulting health damages, expressed in terms of lost quality adjusted life years (QALYs). Resource costs include damages from greenhouse gas-induced climate change, vehicle procurement, infrastructure development, and operations. I find that ECD and CNG produce very similar reductions in health damages compared to CD, although CNG has a modest edge because it may have lower NO x emissions. However, ECD is far more cost effective ($400,000-900,000 cost per QALY saved) than CNG (around $4 million per QALY saved). The results are uncertain because the model used makes a series of simplifying assumptions and because emissions data and cost data for school buses are very limited

  10. Developing compressed natural gas as an automotive fuel in Nigeria: Lessons from international markets

    International Nuclear Information System (INIS)

    Ogunlowo, Olufemi O.; Bristow, Abigail L.; Sohail, M.

    2015-01-01

    The Nigerian government proposed the use of compressed natural gas (CNG) as an automotive fuel in 1997 as part of the initiatives to harness natural gas (NG) resources but progress has been slow. This paper examines the natural gas vehicle (NGV) implementation approaches and outcomes in seven countries with diverse experiences in order to gain an understanding of the barriers to the NGV market development in Nigeria. The analysis employs hermeneutic principles to secondary data derived from academic literature, published reports from a variety of international agencies, grey literature, and text from online sources and identifies eight success factors for NGV market development namely: strategic intent, legal backing, learning and adaptation, assignment of responsibilities, financial incentives, NG pricing, consumer confidence, and NG infrastructure. The paper concludes that the principal impediment to NGV market development in Nigeria is the uncoordinated implementation approach and that greater government involvement is required in setting strategic goals, developing the legal and regulatory frameworks, setting of clear standards for vehicles and refuelling stations as well as assigning responsibilities to specific agencies. Short-term low cost policy interventions identified include widening the existing NG and gasoline price gap and offering limited support for refuelling and retrofitting facilities. - Highlights: • We examined the NGV policies and implementation strategies in selected countries. • The use of legislative mandates help deepen NGV penetration. • Aligning stakeholder interest is critical to NGV adoption. • Making national interest a priority ahead of regional infrastructure is a critical success factor. • Government support drives participation

  11. Power plant including an exhaust gas recirculation system for injecting recirculated exhaust gases in the fuel and compressed air of a gas turbine engine

    Science.gov (United States)

    Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy; Shaffer, Jason Brian; York, William David

    2014-05-13

    A power plant is provided and includes a gas turbine engine having a combustor in which compressed gas and fuel are mixed and combusted, first and second supply lines respectively coupled to the combustor and respectively configured to supply the compressed gas and the fuel to the combustor and an exhaust gas recirculation (EGR) system to re-circulate exhaust gas produced by the gas turbine engine toward the combustor. The EGR system is coupled to the first and second supply lines and configured to combine first and second portions of the re-circulated exhaust gas with the compressed gas and the fuel at the first and second supply lines, respectively.

  12. A complete fuel development facility utilizing a dual core TRIGA reactor system

    Energy Technology Data Exchange (ETDEWEB)

    Middleton, A; Law, G C [General Atomic Co., San Diego, CA (United States)

    1974-07-01

    A TRIGA Dual Core Reactor System has been chosen by the Romanian Government as the heart of a new fuel development facility which will be operated by the Romanian Institute for Nuclear Technologies. The Facility, which will be operational in 1976, is an integral part of the Romanian National Program for Power Reactor Development, with particular emphasis being placed on fuel development. The unique combination of a new 14 MW steady state TRIGA reactor, and the well-proven TRIGA Annular Core Pulsing Reactor (ACPR) in one below-ground reactor pool resulted in a substantial construction cost savings and gives the facility remarkable experimental flexibility. The inherent safety of the TRIGA fuel elements in both reactor cores means that a secondary containment building is not necessary, resulting in further construction cost savings. The 14 MW steady state reactor gives acceptably high neutron fluxes for long- term testing of various prototype fuel-cladding-coolant combinations; and the TRIGA ACPR high pulse capability allows transient testing of fuel specimens, which is so important for accurate prediction of the performance of power reactor fuel elements under postulated failure conditions. The 14 MW steady state reactor has one large and three small in-core irradiation loop positions, two large irradiation loop positions adjacent to the core face, and twenty small holes in the beryllium reflector for small capsule irradiation. The power level of 14 MW will yield peak unperturbed thermal neutron fluxes in the central experiment position approaching 3.0 x 10{sup 14} n/cm{sup 2}-sec. The ACPR has one large dry central experimental cavity which can be loaded at pool level through a shielded offset loading tube; a small diameter in-core flux trap; and an in-core pneumatically-operated capsule irradiation position. A peak pulse of 15,000 MW will yield a peak fast neutron flux in the central experimental cavity of about 1.5 x 10{sup 17} n/cm{sup 2}-sec. The pulse width at

  13. EFFECT OF INJECTOR OPENING PRESSURE ON PERFORMANCE AND EMISSION OF LPG - METHYL ESTER OF MAHUA OIL DUAL FUEL ENGINE

    Directory of Open Access Journals (Sweden)

    N. Kapilan

    2017-11-01

    Full Text Available One of variables, which affect the performance and emission of dual fuel engine is injection pressure. Hence in the present work, effect of Injector opening pressure on the performance of the engine was studied.  A four stroke single cylinder engine was modified to work in dual fuel mode. Three injector opening pressures (180 bar, 200 bar and 220 bar were considered for the present work. Methyl ester of mahua oil was used as pilot fuel and LPG was used as primary fuel.    From the test results, it was observed that the injector opening pressure of 200 bar results in higher brake thermal efficiency. The higher injector opening pressure results in better atomization and peneatration of methyl ester of mahua oil. The exhaust emissions such as Smoke, unburnt hydro carbon and carbon monoxide of 200 bar is lower than other pressures.

  14. Experimental Analysis of a Small Generator set Operating on Dual Fuel Diesel-Ethanol

    Directory of Open Access Journals (Sweden)

    Marcel Alex Vailatti

    2017-08-01

    Full Text Available This work aims to analyze the operation of a generator set on single fuel mode with diesel oil, and on dual fuel mode using diesel–ethanol blends. The engine used to realize the experimental analysis was a diesel cycle model, single cylinder, direct injection, air refrigerated and coupled to a three-phase electric generator, whose set capacity was 8.0 kVA. The generated electric energy was dissipated in electrical resistances inside a reservoir with running water. Fuels were blended in different volumetric ratios, using a small portion of vegetable castor oil to promote the homogenization. The percentages of substitutions of diesel oil were by 10% to 50%, increasing by 10% the replacement for each sample. Also, the engine was operated with 100% substitution of diesel oil, i.e., for this condition, the samples were composed of ethanol/castor oil 90/10 (volume/volume, 80/20 and 75/25. The blends of diesel and ethanol did not obtain good performance, mainly in taxes of substitution above 40%, causing combustion failures, operational instability, and increase of fuel consumption, although it has achieved a greatly reduction on opacity percentages. The blends with 100% of substitution of diesel oil obtained good performance except to blend with 90% ethanol, where occurred combustion failures, which caused operational instability. To these conditions, the results achieved are increase of consumption by 17%, decrease of opacity by 79%, decrease of exhaust gas temperature by 3.5% and increase of engine thermal efficiency by 1.3%. At the ethanol – castor oil blends there was a decrease in the percentage of opacity by 96%, decrease of exhaust gas temperature by 17.6%, with a minimum of operational irregularities, although fuel consumption has increased by 52.4% and the engine thermal efficiency has decreased almost 1.7%.

  15. Application of Alcohols to Dual - Fuel Feeding the Spark-Ignition and Self-Ignition Engines

    Directory of Open Access Journals (Sweden)

    Stelmasiak Zdzisław

    2014-10-01

    Full Text Available This paper concerns analysis of possible use of alcohols for the feeding of self - ignition and spark-ignition engines operating in a dual- fuel mode, i.e. simultaneously combusting alcohol and diesel oil or alcohol and petrol. Issues associated with the requirements for application of bio-fuels were presented with taking into account National Index Targets, bio-ethanol production methods and dynamics of its production worldwide and in Poland. Te considerations are illustrated by results of the tests on spark- ignition and self- ignition engines fed with two fuels: petrol and methanol or diesel oil and methanol, respectively. Te tests were carried out on a 1100 MPI Fiat four- cylinder engine with multi-point injection and a prototype collector fitted with additional injectors in each cylinder. Te other tested engine was a SW 680 six- cylinder direct- injection diesel engine. Influence of a methanol addition on basic operational parameters of the engines and exhaust gas toxicity were analyzed. Te tests showed a favourable influence of methanol on combustion process of traditional fuels and on some operational parameters of engines. An addition of methanol resulted in a distinct rise of total efficiency of both types of engines at maintained output parameters (maximum power and torque. In the same time a radical drop in content of hydrocarbons and nitrogen oxides in exhaust gas was observed at high shares of methanol in feeding dose of ZI (petrol engine, and 2-3 fold lower smokiness in case of ZS (diesel engine. Among unfavourable phenomena, a rather insignificant rise of CO and NOx content for ZI engine, and THC and NOx - for ZS engine, should be numbered. It requires to carry out further research on optimum control parameters of the engines. Conclusions drawn from this work may be used for implementation of bio-fuels to feeding the combustion engines.

  16. Effects of ethanol added fuel on exhaust emissions and combustion in a premixed charge compression ignition diesel engine

    Directory of Open Access Journals (Sweden)

    Kim Yungjin

    2015-01-01

    Full Text Available The use of diesel engines for vehicle has been increasing recently due to its higher thermal efficiency and lower CO2 emission level. However, in the case of diesel engine, NOx increases in a high temperature combustion region and particulate matter is generated in a fuel rich region. Therefore, the technique of PCCI (premixed charge compression ignition is often studied to get the peak combustion temperature down and to make a better air-fuel mixing. However it also has got a limited operating range and lower engine power produced by the wall wetting and the difficulty of the ignition timing control. In this research, the effect of injection strategies on the injected fuel behavior, combustion and emission characteristics in a PCCI engine were investigated to find out the optimal conditions for fuel injection, and then ethanol blended diesel fuel was used to control the ignition timing. As a result, the combustion pressures and ROHR (rate of heat release of the blended fuel became lower, however, IMEP showed fewer differences. Especially in the case of triple injection, smoke could be reduced a little and NOx emission decreased a lot by using the ethanol blended fuel simultaneously without much decreasing of IMEP compared to the result of 100% diesel fuel.

  17. IMPLEMENTATION OF DIOXANE AND DIESEL FUEL BLENDS TO REDUCE EMISSION AND TO IMPROVE PERFORMANCE OF THE COMPRESSION IGNITION ENGINE

    OpenAIRE

    SENDILVELAN S.; SUNDAR RAJ C.

    2017-01-01

    Performance of a compression ignition engine fuelled with 1, 4 Dioxane- diesel blends is evaluated. A single-cylinder, air-cooled, direct injection diesel engine developing a power output of 5.2 kW at 1500 rev/min is used. Base data is generated with standard diesel fuel subsequently; five fuel blends namely 90:10, 80:20, 70:30, 60:40 and 50:50 percentages by volume of diesel and dioxane were prepared and tested in the diesel engine. Engine performance and emission data were used to optimize ...

  18. Comparison of thermal and radical effects of EGR gases on combustion process in dual fuel engines at part loads

    International Nuclear Information System (INIS)

    Pirouzpanah, V.; Khoshbakhti Saray, R.; Sohrabi, A.; Niaei, A.

    2007-01-01

    Dual fuel engines at part load inevitably suffer from lower thermal efficiency and higher emission of carbon monoxide and unburned fuel. This work is conducted to investigate the combustion characteristics of a dual fuel (Diesel-gas) engine at part loads using a single zone combustion model with detailed chemical kinetics for combustion of natural gas fuel. In this home made software, the presence of the pilot fuel is considered as a heat source that is deriving form two superposed Wiebe's combustion functions to account for its contribution to ignition of the gaseous fuel and the rest of the total released energy. The chemical kinetics mechanism consists of 112 reactions with 34 species. This combustion model is able to establish the development of the combustion process with time and the associated important operating parameters, such as pressure, temperature, heat release rate (HRR) and species concentration. Therefore, this work is an attempt to investigate the combustion phenomenon at part load and using exhaust gas recirculation (EGR) to improve the above mentioned problems. Also, the results of this work show that each of the different cases of EGR (thermal, chemical and radical cases) has an important role on the combustion process in dual fuel engines at part loads. It is found that all the different cases of EGR have positive effects on the performance and emission parameters of dual fuel engines at part loads despite the negative effect of some diluent gases in the chemical case, which moderates too much the positive effects of the thermal and radical cases of EGR. Predicted values show good agreement with corresponding experimental values over the whole range of engine operating conditions. Implications will be discussed in detail

  19. Particulate Matter Emission from Dual Fuel Diesel Engine Fuelled with Natural Gas

    Directory of Open Access Journals (Sweden)

    Stelmasiak Zdzisław

    2017-06-01

    Full Text Available The paper presents the results of examination of particulate matter emission from the Diesel engine FPT 1.3 MJT simultaneously fuelled with diesel oil and natural gas CNG. The basic premise for engine adaptation was the addition of a small amount of CNG to reduce exhaust gas opacity and particulate matter emission. At this assumption, diesel oil remained the basic fuel, with contribution amounting to 0,70-0,85 of total energy delivered to the engine. The dual fuel engine was examined using an original controller installed in the Diesel engine FPT 1.3 MJT which controlled the diesel fuel dose. The dose of the injected natural gas was controlled by changing the opening time of gas injectors at constant pressure in the gas collector. The examined issues included the exhaust gas opacity, and the total number and fractional distribution of the emitted particles. The measurements were performed at twenty selected measuring points corresponding to the New European Driving Cycle (NEDC test. The performed tests have demonstrated a positive effect of gas addition on exhaust gas opacity and particulate matter emission. Depending on test conditions, the exhaust gas opacity was reduced by 10÷92%, and the total number of particles by 30÷40%. The performed tests have revealed that a small addition of gas can reduce the load of the DPF filter, extend its lifetime, and increase engine reliability. Longer time intervals between successive DPF filter regenerations improve ecological properties of the engine.

  20. Development of a 1200 KW/CYL low pressure dual fuel engine for LNG carriers

    Energy Technology Data Exchange (ETDEWEB)

    Grosshans, G. [S.E.M.T.-Pielstick, Thermodynamical Project Dept. (France)

    1998-12-31

    This paper describes the design and feasibility tests of a 570 mm bore 4 stroke low pressure (L.P.) dual fuel engine rated at 20.9 bar BMEP meant for the propulsion of LNG carriers. The basic design features which are to be in accordance with classification societies safety rules are described: individual electro hydraulic valves located in the air manifold ducts, pilot injection, monitoring system etc. The engine capability to burn variable liquid/gas fuel proportions have been investigated with diesel oil and heavy fuel and possible running zones are defined. This ensures the possibility of the engine to cope with the different boil off gas quantity emanating from the ship`s tank during her loaded - and ballast - journeys. With the very lean setting of this engine, no adverse influence of the high ash lube-oil additives were found during the tests. Further tests are necessary to confirm that possible more significant fouling of the combustion chamber is still acceptable. (au)

  1. Experimental and modelling study of reverse flow catalytic converters for natural gas/diesel dual fuel engine pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B.

    2000-07-01

    There is renewed interest in the development of natural gas vehicles in response to the challenge to reduce urban air pollution and consumption of petroleum. The natural gas/diesel dual fuel engine is one way to apply natural gas to the conventional diesel engine. Dual fuel engines operating on natural gas and diesel emit less nitrogen oxides, and less carbon soot to the air compared to conventional diesel engines. The problem is that at light loads, fuel efficiency is reduced and emissions of hydrocarbons and carbon monoxide are increased. This thesis focused on control methods for emissions of hydrocarbons and carbon monoxide in the dual fuel engine at light loads. This was done by developing a reverse flow catalytic converter to complement dual fuel engine exhaust characteristics. Experimental measurements and numerical simulations of reverse flow catalytic converters were conducted. Reverse flow creates a high reactor temperature even when the engine is run at low exhaust temperature levels at light loads. The increase in reactor temperature from reverse flow could be 2 or 3 times higher than the adiabatic temperature increase, which is based on the reactor inlet temperature and concentration. This temperature makes it possible for greater than 90 per cent of the hydrocarbon and carbon monoxide to be converted with a palladium based catalyst. Reverse flow appears to be better than conventional unidirectional flow to deal with natural gas/diesel dual fuel engine pollution at light loads. Reverse flow could also maintain reactor temperature at over 800 K and hydrocarbon conversion at about 80 per cent during testing. The newly presented model simulates reactor performance with reasonable accuracy. Both carbon monoxide and methane oxidation over the palladium catalyst in excess oxygen and water were described using first order kinetics.

  2. Fossil fuel subsidy reform in the WTO : Options for constraining dual pricing in the multilateral trading system

    NARCIS (Netherlands)

    Marhold, Anna

    2017-01-01

    Fossil fuel subsidies harm the environment, add to health hazards caused by air pollution, and delay the energy transition. Scholars and practitioners have therefore been exploring ways to reform and eliminate them. This paper discusses the practice of energy dual pricing in the broader context of

  3. Effect of fuel injection parameters on combustion stability and emissions of a mineral diesel fueled partially premixed charge compression ignition (PCCI) engine

    International Nuclear Information System (INIS)

    Jain, Ayush; Singh, Akhilendra Pratap; Agarwal, Avinash Kumar

    2017-01-01

    Highlights: • NOx and PM emissions were lowest at 700 bar fuel injection pressure (FIP). • PCCI showed lower knocking than compression ignition combustion mode. • Increasing FIP reduced emissions of nitrogen oxides and smoke opacity in PCCI mode. • Increasing FIP reduced nucleation mode particle concentration. • Increasing FIP with advanced main injection timings improved PCCI combustion. - Abstract: This experimental study focuses on developing new combustion concept for compression ignition (CI) engines by achieving partially homogeneous charge, leading to low temperature combustion (LTC). Partially premixed charge compression ignition (PCCI) combustion is a single-stage phenomenon, with combustion shifting towards increasingly premixed combustion phase, resulting in lower in-cylinder temperatures. PCCI leads to relatively lower emissions of oxides of nitrogen (NOx) and particulate matter (PM) simultaneously. To investigate combustion, performance and emission characteristics of the PCCI engine, experiments were performed in a mineral diesel fueled single cylinder research engine, which was equipped with flexible fuel injection equipment (FIE). Effects of fuel injection pressure (FIP) were investigated by changing the FIP from 400 bar to 1000 bar. Experiments were carried out by varying start of main injection (SoMI) timings (from 12° to 24° before top dead center (bTDC)), when using single pilot injection. This experimental study included detailed investigations of particulate characteristics such as particulate number-size distribution using engine exhaust particle sizer (EEPS), particulate bound trace metal analysis using inductively coupled plasma-optical emission spectrometer (ICP-OES), and soot morphology using transmission electron microscopy (TEM). PCCI combustion improved with increasing FIP (up to 700 bar) due to superior fuel atomization however further increasing FIP deteriorated PCCI combustion and engine performance due to intense

  4. Numerical Investigation of a Gasoline-Like Fuel in a Heavy-Duty Compression Ignition Engine Using Global Sensitivity Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Pinaki; Probst, Daniel; Pei, Yuanjiang; Zhang, Yu; Traver, Michael; Cleary, David; Som, Sibendu

    2017-03-28

    Fuels in the gasoline auto-ignition range (Research Octane Number (RON) > 60) have been demonstrated to be effective alternatives to diesel fuel in compression ignition engines. Such fuels allow more time for mixing with oxygen before combustion starts, owing to longer ignition delay. Moreover, by controlling fuel injection timing, it can be ensured that the in-cylinder mixture is “premixed enough” before combustion occurs to prevent soot formation while remaining “sufficiently inhomogeneous” in order to avoid excessive heat release rates. Gasoline compression ignition (GCI) has the potential to offer diesel-like efficiency at a lower cost and can be achieved with fuels such as low-octane straight run gasoline which require significantly less processing in the refinery compared to today’s fuels. To aid the design and optimization of a compression ignition (CI) combustion system using such fuels, a global sensitivity analysis (GSA) was conducted to understand the relative influence of various design parameters on efficiency, emissions and heat release rate. The design parameters included injection strategies, exhaust gas recirculation (EGR) fraction, temperature and pressure at intake valve closure and injector configuration. These were varied simultaneously to achieve various targets of ignition timing, combustion phasing, overall burn duration, emissions, fuel consumption, peak cylinder pressure and maximum pressure rise rate. The baseline case was a three-dimensional closed-cycle computational fluid dynamics (CFD) simulation with a sector mesh at medium load conditions. Eleven design parameters were considered and ranges of variation were prescribed to each of these. These input variables were perturbed in their respective ranges using the Monte Carlo (MC) method to generate a set of 256 CFD simulations and the targets were calculated from the simulation results. GSA was then applied as a screening tool to identify the input parameters having the most

  5. Reversing flow catalytic converter for a natural gas/diesel dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Liu, E.; Checkel, M.D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Mechanical Engineering; Hayes, R.E. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Alberta Univ., Edmonton, AB (Canada). Dept. of Mechanical Engineering; Zheng, M.; Mirosh, E. [Alternative Fuel Systems Inc., Calgary, AB (Canada)

    2001-07-01

    An experimental and modelling study was performed for a reverse flow catalytic converter attached to a natural gas/diesel dual fuel engine. The catalytic converter had a segmented ceramic monolith honeycomb substrate and a catalytic washcoat containing a predominantly palladium catalyst. A one-dimensional single channel model was used to simulate the operation of the converter. The kinetics of the CO and methane oxidation followed first-order behaviour. The activation energy for the oxidation of methane showed a change with temperature, dropping from a value of 129 to 35 kJ/mol at a temperature of 874 K. The reverse flow converter was able to achieve high reactor temperature under conditions of low inlet gas temperature, provided that the initial reactor temperature was sufficiently high. (author)

  6. Treatment of soak liquor and bioelectricity generation in dual chamber microbial fuel cell.

    Science.gov (United States)

    Sathishkumar, Kuppusamy; Narenkumar, Jayaraman; Selvi, Adikesavan; Murugan, Kadarkarai; Babujanarthanam, Ranganathan; Rajasekar, Aruliah

    2018-02-08

    The discharge of untreated soak liquor from tannery industry causes severe environmental pollution. This study is characterizing the soak liquor as a substrate in the microbial fuel cell (MFC) for remediation along with electricity generation. The dual chamber MFC was constructed and operated. Potassium permanganate was used as cathode solution and carbon felt electrode as anodic and cathodic material, respectively. The soak liquor was characterized by electrochemical studies viz., cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and polarization studies, respectively. The removal percentage of protein, lipid, and chemical oxygen demand (COD) were measured before and after treatment with MFC. The results of MFC showed a highest current density of 300 mA/cm 2 and a power density of 92 mW/m 2 . The removal of COD, protein, and lipid were noted as 96, 81, and 97% respectively during MFC process. This MFC can be used in tannery industries for treating soak liquor and simultaneous electricity generation.

  7. Combustion and exhaust emission characteristics of a compression ignition engine using liquefied petroleum gas-Diesel blended fuel

    International Nuclear Information System (INIS)

    Qi, D.H.; Bian, Y.ZH.; Ma, ZH.Y.; Zhang, CH.H.; Liu, SH.Q.

    2007-01-01

    Towards the effort of reducing pollutant emissions, especially smoke and nitrogen oxides, from direct injection (DI) Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. The use of liquefied petroleum gas (LPG) as an alternative fuel is a promising solution. The potential benefits of using LPG in Diesel engines are both economical and environmental. The high auto-ignition temperature of LPG is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under LPG-Diesel blended fuel conditions, using LPG-Diesel blended fuels with various blended rates (0%, 10%, 20%, 30%, 40%). Comparative results are given for various engine speeds and loads for conventional Diesel and blended fuels, revealing the effect of blended fuel combustion on engine performance and exhaust emissions

  8. Dual application of duckweed and azolla plants for wastewater treatment and renewable fuels and petrochemicals production

    Science.gov (United States)

    2014-01-01

    Background Shortages in fresh water supplies today affects more than 1 billion people worldwide. Phytoremediation strategies, based on the abilities of aquatic plants to recycle nutrients offer an attractive solution for the bioremediation of water pollution and represents one of the most globally researched issues. The subsequent application of the biomass from the remediation for the production of fuels and petrochemicals offers an ecologically friendly and cost-effective solution for water pollution problems and production of value-added products. Results In this paper, the feasibility of the dual application of duckweed and azolla aquatic plants for wastewater treatment and production of renewable fuels and petrochemicals is explored. The differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by these aquatic macrophytes were used as the basis for optimization of the composition of wastewater effluents. Analysis of pyrolysis products showed that azolla and algae produce a similar range of bio-oils that contain a large spectrum of petrochemicals including straight-chain C10-C21 alkanes, which can be directly used as diesel fuel supplement, or a glycerin-free component of biodiesel. Pyrolysis of duckweed produces a different range of bio-oil components that can potentially be used for the production of “green” gasoline and diesel fuel using existing techniques, such as catalytic hydrodeoxygenation. Conclusions Differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by different aquatic macrophytes can be used for optimization of composition of wastewater effluents. The generated data suggest that the composition of the petrochemicals can be modified in a targeted fashion, not only by using different species, but also by changing the source plants’ metabolic profile, by exposing them to different abiotic or biotic stresses. This study presents an attractive, ecologically friendly and cost

  9. Dual application of duckweed and azolla plants for wastewater treatment and renewable fuels and petrochemicals production.

    Science.gov (United States)

    Muradov, Nazim; Taha, Mohamed; Miranda, Ana F; Kadali, Krishna; Gujar, Amit; Rochfort, Simone; Stevenson, Trevor; Ball, Andrew S; Mouradov, Aidyn

    2014-02-28

    Shortages in fresh water supplies today affects more than 1 billion people worldwide. Phytoremediation strategies, based on the abilities of aquatic plants to recycle nutrients offer an attractive solution for the bioremediation of water pollution and represents one of the most globally researched issues. The subsequent application of the biomass from the remediation for the production of fuels and petrochemicals offers an ecologically friendly and cost-effective solution for water pollution problems and production of value-added products. In this paper, the feasibility of the dual application of duckweed and azolla aquatic plants for wastewater treatment and production of renewable fuels and petrochemicals is explored. The differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by these aquatic macrophytes were used as the basis for optimization of the composition of wastewater effluents. Analysis of pyrolysis products showed that azolla and algae produce a similar range of bio-oils that contain a large spectrum of petrochemicals including straight-chain C10-C21 alkanes, which can be directly used as diesel fuel supplement, or a glycerin-free component of biodiesel. Pyrolysis of duckweed produces a different range of bio-oil components that can potentially be used for the production of "green" gasoline and diesel fuel using existing techniques, such as catalytic hydrodeoxygenation. Differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by different aquatic macrophytes can be used for optimization of composition of wastewater effluents. The generated data suggest that the composition of the petrochemicals can be modified in a targeted fashion, not only by using different species, but also by changing the source plants' metabolic profile, by exposing them to different abiotic or biotic stresses. This study presents an attractive, ecologically friendly and cost-effective solution for efficient bio

  10. Cycle to Cycle Variation Study in a Dual Fuel Operated Engine

    KAUST Repository

    Pasunurthi, Shyamsundar

    2017-03-28

    The standard capability of engine experimental studies is that ensemble averaged quantities like in-cylinder pressure from multiple cycles and emissions are reported and the cycle to cycle variation (CCV) of indicated mean effective pressure (IMEP) is captured from many consecutive combustion cycles for each test condition. However, obtaining 3D spatial distribution of all the relevant quantities such as fuel-air mixing, temperature, turbulence levels and emissions from such experiments is a challenging task. Computational Fluid Dynamics (CFD) simulations of engine flow and combustion can be used effectively to visualize such 3D spatial distributions. A dual fuel engine is considered in the current study, with manifold injected natural gas (NG) and direct injected diesel pilot for ignition. Multiple engine cycles in 3D are simulated in series like in the experiments to investigate the potential of high fidelity RANS simulations coupled with detailed chemistry, to accurately predict the CCV. Cycle to cycle variation (CCV) is expected to be due to variabilities in operating and boundary conditions, in-cylinder stratification of diesel and natural gas fuels, variation in in-cylinder turbulence levels and velocity flow-fields. In a previous publication by the authors [1], variabilities in operating and boundary conditions are incorporated into several closed cycle simulations performed in parallel. Stochastic variations/stratifications of fuel-air mixture, turbulence levels, temperature and internal combustion residuals cannot be considered in such closed cycle simulations. In this study, open cycle simulations with port injection of natural gas predicted the combined effect of the stratifications on the CCV of in-cylinder pressure. The predicted Coefficient of Variation (COV) of cylinder pressure is improved compared to the one captured by closed cycle simulations in parallel.

  11. Experimental analysis of ethanol dual-fuel combustion in a heavy-duty diesel engine: An optimisation at low load

    International Nuclear Information System (INIS)

    Pedrozo, Vinícius B.; May, Ian; Dalla Nora, Macklini; Cairns, Alasdair; Zhao, Hua

    2016-01-01

    Highlights: • Dual-fuel combustion offers promising results on a stock heavy-duty diesel engine. • The use of split diesel injections extends the benefits of the dual-fuel mode. • Ethanol–diesel dual-fuel combustion results in high indicated efficiencies. • NOx and soot emissions are significantly reduced. • Combustion efficiency reaches 98% with an ethanol energy ratio of 53%. - Abstract: Conventional diesel combustion produces harmful exhaust emissions which adversely affect the air quality if not controlled by in-cylinder measures and exhaust aftertreatment systems. Dual-fuel combustion can potentially reduce the formation of nitrogen oxides (NOx) and soot which are characteristic of diesel diffusion flame. The in-cylinder blending of different fuels to control the charge reactivity allows for lower local equivalence ratios and temperatures. The use of ethanol, an oxygenated biofuel with high knock resistance and high latent heat of vaporisation, increases the reactivity gradient. In addition, renewable biofuels can provide a sustainable alternative to petroleum-based fuels as well as reduce greenhouse gas emissions. However, ethanol–diesel dual-fuel combustion suffers from poor engine efficiency at low load due to incomplete combustion. Therefore, experimental studies were carried out at 1200 rpm and 0.615 MPa indicated mean effective pressure on a heavy-duty diesel engine. Fuel delivery was in the form of port fuel injection of ethanol and common rail direct injection of diesel. The objective was to improve combustion efficiency, maximise ethanol substitution, and minimise NOx and soot emissions. Ethanol energy fractions up to 69% were explored in conjunction with the effect of different diesel injection strategies on combustion, emissions, and efficiency. Optimisation tests were performed for the optimum fuelling and diesel injection strategy. The resulting effects of exhaust gas recirculation, intake air pressure, and rail pressure were

  12. Experimental and theoretical analysis of the combustion process at low loads of a diesel natural gas dual-fuel engine

    International Nuclear Information System (INIS)

    Li, Weifeng; Liu, Zhongchang; Wang, Zhongshu

    2016-01-01

    To construct an effective method to analyze the combustion process of dual fuel engines at low loads, effects of combustion boundaries on the combustion process of an electronically controlled diesel natural gas dual-fuel engine at low loads were investigated. Three typical combustion modes, including h, m and n, appeared under different combustion boundaries. In addition, the time-sequenced characteristic and the heat release rate-imbalanced characteristic were found in the dual fuel engine combustion process. To quantify these characteristics, two quantitative indicators, including the TSC (time-sequenced coefficient) and the HBC (HRR-balanced coefficient) were defined. The results show that increasing TSC and HBC can decrease HC (hydrocarbon) emissions and improve the BTE (brake thermal efficiency) significantly. The engine with the n combustion mode can obtain the highest BTE and the lowest HC emissions, followed by m, and then h. However, the combustion process of the engine will deteriorate sharply if boundary conditions are not strictly controlled in the n combustion mode. Based on the n combustion mode, advancing the start of diesel injection significantly, using large EGR (exhaust gas recirculation) rate and appropriately intake throttling can effectively reduce HC emissions and improve the BTE of dual fuel engines at low loads with relatively high natural gas PES (percentage energy substitution). - Highlights: • We reported three typical combustion modes of a dual-fuel engine at low loads. • Time-sequenced characteristic was put forward and qualified. • HRR-imbalanced characteristic was put forward and qualified. • Three combustion modes appeared as equivalence ratio/diesel injection timing varied. • The engine performance varied significantly with different combustion mode.

  13. The influence of the mechanical properties on fuel rod support characteristics – A case study of dual cooled fuel

    International Nuclear Information System (INIS)

    Kim, Jae Yong; Kim, Hyung Kyu; Ko, Sung Ho

    2014-01-01

    Highlights: • Spring characterization test and analysis were performed to obtain characteristic curves of modified H-type spring. • Using an actual mechanical property is needed to correctly predict the spring characteristics. • The characteristics during unloading should be used for a spacer grid support design. - Abstract: This paper concerns a finite element analysis for a spacer grid support (spring and dimple) design. An accurate prediction of the support characteristics (contact force vs. deflection) is the most crucial in the design by analysis. It is found that the mechanical properties are the key parameter to simulate the characteristics as close as the experimental results after using three different sets of mechanical property data including the actual tensile test results of the present material for a spacer grid of a dual cooled fuel. Besides, the validity of using the characteristics during unloading process is also discussed incorporating a possible overshoot of the support. The coincidence between the present finite element prediction and experimental results is quite good: less than 3.09% at most

  14. Modification Design of Petrol Engine for Alternative Fueling using Compressed Natural Gas

    Directory of Open Access Journals (Sweden)

    Eliezer Uchechukwu Okeke

    2013-04-01

    Full Text Available This paper is on the modification design of petrol engine for alternative fuelling using Compressed Natural Gas (CNG. It provides an analytical background in the modification design process. A petrol engine Honda CR-V 2.0 auto which has a compression ratio of 9.8 was selected as case study. In order for this petrol engine to run on CNG, its compression had to be increased. An optimal compression ratio of 11.97 was computed using the standard temperature-specific volume relationship for an isentropic compression process. This computation of compression ratio is based on an inlet air temperature of 30oC (representative of tropical ambient condition and pre-combustion temperature of 540oC (corresponding to the auto-ignition temperature of CNG. Using this value of compression ratio, a dimensional modification Quantity =1.803mm was obtained using simple geometric relationships. This value of 1.803mm is needed to increase the length of the connecting rod, the compression height of the piston or reducing the sealing plate’s thickness. After the modification process, a CNG engine of air standard efficiency 62.7% (this represents a 4.67% increase over the petrol engine, capable of a maximum power of 83.6kW at 6500rpm, was obtained.

  15. Effect of palm oil fuel ash on compressive strength of palm oil boiler stone lightweight aggregate concrete

    Science.gov (United States)

    Muthusamy, K.; Zamri, N. A.; Kusbiantoro, A.; Lim, N. H. A. S.; Ariffin, M. A. Mohd

    2018-04-01

    Both palm oil fuel ash (POFA) and palm oil boiler stone (POBS) are by-products which has been continuously generated by local palm oil mill in large amount. Both by products is usually disposed as profitless waste and considered as nuisance to environment. The present research investigates the workability and compressive strength performance of lightweight aggregate concrete (LWAC) made of palm oil boiler stone (POBS) known as palm oil boiler stone lightweight aggregate concrete (POBS LWAC) containing various content of palm oil fuel ash. The control specimen that is POBS LWAC of grade 60 were produced using 100% OPC. Then, another 4 mixes were prepared by varying the POFA percentage from 10%, 20%, 30% and 40% by weight of cement. Fresh mixes were subjected to slump test to determine its workability before casted in form of cubes. Then, all specimens were subjected to water curing up to 28 days and then tested for its compressive strength. It was found out that utilizing of optimum amount of POFA in POBS LWAC would improve the workability and compressive strength of the concrete. However, inclusion of POFA more than optimum amount is not recommended as it will increase the water demand leading to lower workability and strength reduction.

  16. Manufacturing of FeCrAl/Zr Dual Layer tube for its application to LWR Fuel cladding

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dong Jun; Lim, Do Wan; Jung, Yang Il; Kim, Hyun Gil; Park, Jeong Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    Many advanced materials such as MAX phases, Mo, SiC, and Fe-based alloys are being considered a possible candidate to substitute the Zr-based alloy cladding has been used in light water reactors. Among the proposed candidate materials, Fe-based alloy is one of the most promising candidates owing to its excellent formability, very good high strength, and corrosion resistance at high temperature. However, neutron cross section of FeCrAl alloy is much higher than that of existing Zr-based alloys. In this study, FeCrAl/Zr dual layer tube was manufactured by using a hot isostatic pressing (HIP) method. The thickness of outer FeCrAl layer was varied from 50 to 250 μm but all the FeCrAl/Zr dual layer tube samples maintained its total thickness of 570 μm. For a detailed microstructural characterization of FeCrAl/Zr dual layer, polarized optical microscopy and scanning electron microscopy (SEM) study carried out and its mechanical property was measured by ring compression test. FeCrAl/Zr dual layer tube sample was successfully manufactured with good adhesion between both layers. Inter layer showing gradual element variation was observed at interface. Result obtained from simulated LOCA test indicates that FeCrAl/Zr dual layer tube may maintain its integrity during LOCA and its accident tolerance had greatly improved compared to that of Zr-based alloy.

  17. Experimental investigation and combustion analysis of a direct injection dual-fuel diesel-natural gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Carlucci, A.P.; De Risi, A.; Laforgia, D.; Naccarato, F. [Department of Engineering for Innovation, University of Salento, CREA, via per Arnesano, 73100 Lecce (Italy)

    2008-02-15

    A single-cylinder diesel engine has been converted into a dual-fuel engine to operate with natural gas together with a pilot injection of diesel fuel used to ignite the CNG-air charge. The CNG was injected into the intake manifold via a gas injector on purpose designed for this application. The main performance of the gas injector, such as flow coefficient, instantaneous mass flow rate, delay time between electrical signal and opening of the injector, have been characterized by testing the injector in a constant-volume optical vessel. The CNG jet structure has also been characterized by means of shadowgraphy technique. The engine, operating in dual-fuel mode, has been tested on a wide range of operating conditions spanning different values of engine load and speed. For all the tested operating conditions, the effect of CNG and diesel fuel injection pressure, together with the amount of fuel injected during the pilot injection, were analyzed on the combustion development and, as a consequence, on the engine performance, in terms of specific emission levels and fuel consumption. (author)

  18. Modeling the emissions of a dual fuel engine coupled with a biomass gasifier-supplementing the Wiebe function.

    Science.gov (United States)

    Vakalis, Stergios; Caligiuri, Carlo; Moustakas, Konstantinos; Malamis, Dimitris; Renzi, Massimiliano; Baratieri, Marco

    2018-03-12

    There is a growing market demand for small-scale biomass gasifiers that is driven by the economic incentives and the legislative framework. Small-scale gasifiers produce a gaseous fuel, commonly referred to as producer gas, with relatively low heating value. Thus, the most common energy conversion systems that are coupled with small-scale gasifiers are internal combustion engines. In order to increase the electrical efficiency, the operators choose dual fuel engines and mix the producer gas with diesel. The Wiebe function has been a valuable tool for assessing the efficiency of dual fuel internal combustion engines. This study introduces a thermodynamic model that works in parallel with the Wiebe function and calculates the emissions of the engines. This "vis-à-vis" approach takes into consideration the actual conditions inside the cylinders-as they are returned by the Wiebe function-and calculates the final thermodynamic equilibrium of the flue gases mixture. This approach aims to enhance the operation of the dual fuel internal combustion engines by identifying the optimal operating conditions and-at the same time-advance pollution control and minimize the environmental impact.

  19. Highly Efficient and Visible Light Responsive Heterojunction Composites as Dual Photoelectrodes for Photocatalytic Fuel Cell

    Directory of Open Access Journals (Sweden)

    Honghui Pan

    2018-01-01

    Full Text Available In the present work, a novel photocatalytic fuel cell (PFC system involving a dual heterojunction photoelectrodes, viz. polyaniline/TiO2 nanotubes (PANI/TiO2 NTs photoanode and CuO/Co3O4 nanorods (CuO/Co3O4 NRs photocathode, has been designed. Compared to TiO2 NTs electrode of PFC, the present heterojunction design not only enhances the visible light absorption but also offers the higher efficiency in degrading Rhodamine B–a model organic pollutant. The study includes an evaluation of the dual performance of the photoelectrodes as well. Under visible-light irradiation of 3 mW cm−2, the cell composed of the photoanode PANI/TiO2 NTs and CuO/Co3O4 NRs photocathode forms an interior bias of +0.24 V within the PFC system. This interior bias facilitated the transfer of electrons from the photoanode to photocathode across the external circuit and combined with the holes generated therein along with a simultaneous power production. In this manner, the separation of electron/hole pair was achieved in the photoelectrodes by releasing the holes and electrons of PANI/TiO2 NTs photoanode and CuO/Co3O4 NRs photocathode, respectively. Using this PFC system, the degradation of Rhodamine B in aqueous media was achieved to an extent of 68.5% within a reaction duration of a four-hour period besides a simultaneous power generation of 85 μA cm−2.

  20. Converting hazardous organics into clean energy using a solar responsive dual photoelectrode photocatalytic fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jianyong; Li, Jinhua, E-mail: lijinhua@sjtu.edu.cn; Chen, Quanpeng; Bai, Jing; Zhou, Baoxue

    2013-11-15

    Highlights: • A dual photoelcetrode PFC for converting hazardous organics into electricity. • The PFC possesses high cell performance operating in various model compounds. • Parameters were studied for optimization of the PFC performance. • Significant removal rate of chroma was observed in azo dyes solutions. -- Abstract: Direct discharging great quantities of organics into water-body not only causes serious environmental pollution but also wastes energy sources. In this paper, a solar responsive dual photoelectrode photocatalytic fuel cell (PFC{sup 2}) based on TiO{sub 2}/Ti photoanode and Cu{sub 2}O/Cu photocathode was designed for hazardous organics treatment with simultaneous electricity generation. Under solar irradiation, the interior bias voltage produced for the Fermi level difference between photoelectrodes drives photoelectrons of TiO{sub 2}/Ti photoanode to combine with photoholes of Cu{sub 2}O/Cu photocathode through external circuit thus generating electricity. In the meantime, organics are decomposed by photoholes remained at TiO{sub 2}/Ti photoanode. By using various hazardous organics including azo dyes as model pollutants, the PFC showed high converting performance of organics into electricity. For example, in 0.05 M phenol solution, a short-circuit current density 0.23 mA cm{sup −2}, open-circuit voltage 0.49 V, maximum power output 0.36 10{sup −4} W cm{sup −2} was achieved. On the other hand, removal rate of chroma reached 67%, 87% and 63% in 8 h for methyl orange, methylene blue, Congo red, respectively.

  1. IMPLEMENTATION OF DIOXANE AND DIESEL FUEL BLENDS TO REDUCE EMISSION AND TO IMPROVE PERFORMANCE OF THE COMPRESSION IGNITION ENGINE

    Directory of Open Access Journals (Sweden)

    SENDILVELAN S.

    2017-11-01

    Full Text Available Performance of a compression ignition engine fuelled with 1, 4 Dioxane- diesel blends is evaluated. A single-cylinder, air-cooled, direct injection diesel engine developing a power output of 5.2 kW at 1500 rev/min is used. Base data is generated with standard diesel fuel subsequently; five fuel blends namely 90:10, 80:20, 70:30, 60:40 and 50:50 percentages by volume of diesel and dioxane were prepared and tested in the diesel engine. Engine performance and emission data were used to optimize the blends for reducing emission and improving performance. Results show improved performance with B10 blends compared to neat fuel for all conditions of the engine. Other blends recorded marginal decrease in brake thermal efficiency. The maximum efficiency for B30, B50 blends at peak load are 26.3%, 25.2% respectively against 29.1% for sole fuel. NOx emissions were found to be high or the blends. Peak pressure and rate of pressure rise are increased with increase in dioxane ratio due to improved combustion rate. Heat release pattern shows higher premixed combustion rate with the blends. Higher ignition delay and lower combustion duration are found with all blends than neat diesel fuel.

  2. Local Limit Phenomena, Flow Compression, and Fuel Cracking Effects in High-Speed Turbulent Flames

    Science.gov (United States)

    2015-06-01

    e.g. local extinction and re- ignition , interactions between flow compression and fast-reaction induced dilatation (reaction compression ), and to...time as a function of initial temperature in constant-pressure auto - ignition , and (b) the S-curves of perfectly stirred reactors (PSRs), for n...mechanism. The reduction covered auto - ignition and perfectly stirred reactors for equivalence ratio range of 0.5~1.5, initial temperature higher than

  3. Electricity generation from palm oil tree empty fruit bunch (EFB) using dual chamber microbial fuel cell (MFC)

    Science.gov (United States)

    Ghazali, N. F.; Mahmood, N. A. B. N.; Ibrahim, K. A.; Muhammad, S. A. F. S.; Amalina, N. S.

    2017-06-01

    Microbial fuel cell (MFC) has been discovered and utilized in laboratory scale for electricity production based on microbial degradation of organic compound. However, various source of fuel has been tested and recently complex biomass such as lignocellulose biomass has been focused on. In the present research, oil palm tree empty fruit bunch (EFB) has been tested for power production using dual chamber MFC and power generation analysis has been conducted to address the performance of MFC. In addition, two microorganisms (electric harvesting microbe and cellulose degrading microbe) were used in the MFC operation. The analysis include voltage produced, calculated current and power. The first section in your paper

  4. Numerical Study of the Performance and Emission of a Diesel-Syngas Dual Fuel Engine

    Directory of Open Access Journals (Sweden)

    Shiquan Feng

    2017-01-01

    Full Text Available Based on the theory of direct relation graph (DRG and the sensitivity analysis, a reduced mechanism for the diesel-syngas dual fuel was constructed. Three small thresholds were applied in the process of the detailed mechanism simplification by DRG, and a skeletal mechanism with 185 elements and the 832 elementary reactions was obtained. According to the framework of the skeletal mechanism, the time-consuming approach of sensitivity analysis was employed for further simplification, and the skeletal mechanism was further reduced to the size of 158 elements and 705 reactions. The Chemkin software with the detailed mechanism was utilized to calculate the effect of syngas addition on the combustion characteristics of diesel combustion. The findings showed that the addition of syngas could reduce the ignition delay time and increase the laminar flame speed. Based on the reduced mechanism and engine parameters, a 3D model of the engine was constructed with the Forte code. The 3D model was adopted to study the effect of syngas addition on the performance and exhaust emissions of the engine and the relevant data of the experiment was used in the calibration of the 3D model.

  5. Converting hazardous organics into clean energy using a solar responsive dual photoelectrode photocatalytic fuel cell.

    Science.gov (United States)

    Li, Jianyong; Li, Jinhua; Chen, Quanpeng; Bai, Jing; Zhou, Baoxue

    2013-11-15

    Direct discharging great quantities of organics into water-body not only causes serious environmental pollution but also wastes energy sources. In this paper, a solar responsive dual photoelectrode photocatalytic fuel cell (PFC(2)) based on TiO2/Ti photoanode and Cu2O/Cu photocathode was designed for hazardous organics treatment with simultaneous electricity generation. Under solar irradiation, the interior bias voltage produced for the Fermi level difference between photoelectrodes drives photoelectrons of TiO2/Ti photoanode to combine with photoholes of Cu2O/Cu photocathode through external circuit thus generating electricity. In the meantime, organics are decomposed by photoholes remained at TiO2/Ti photoanode. By using various hazardous organics including azo dyes as model pollutants, the PFC showed high converting performance of organics into electricity. For example, in 0.05 M phenol solution, a short-circuit current density 0.23 mA cm(-2), open-circuit voltage 0.49 V, maximum power output 0.3610(-4)W cm(-2) was achieved. On the other hand, removal rate of chroma reached 67%, 87% and 63% in 8h for methyl orange, methylene blue, Congo red, respectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Experimental study on two-stage air supply downdraft gasifier and dual fuel engine system

    Energy Technology Data Exchange (ETDEWEB)

    Nhuchhen, Daya Ram; Salam, P.A. [Asian Institute of Technology, Energy Field of Study, School of Environment Resource and Development, P. O. Box 4, Klong Luang, Pathumthani (Thailand)

    2012-06-15

    Biomass is a widely used renewable energy resource with net balanced carbon dioxide absorptions and emissions. An inefficient use of solid biomass in combustion process emits more gaseous pollutants, increasing the pollution level. Biomass gasification is one of the techniques to support efficient use of biomass. Multistage gasification is a method of gasification to improve quality of the producer gas in which two separate reactors are designed for separating gasification reactions. This study presents experimental results of gasification using Eucalyptus wood in a single long cylindrical reactor with two air supply ports, i.e., primary and secondary. The effect of different air supply rates on the heating values of the producer gas was studied. Optimum primary and secondary air supply rate of 100 and 80 l/min at equivalence ratio of 0.38 was observed with producer gas lower heating value of 4.72 MJ Nm{sup -3}. The performance of a diesel engine in the dual fuel mode was also evaluated. The overall gasifier engine system efficiency was 13.86 % at an electrical load of 10.54 kW{sub e} with specific energy consumption of 16.22 MJ kWh{sup -1}. The heat recovery system was designed and tested to recover heat from producer gas in the form of hot water. (orig.)

  7. Minimum Specific Fuel Consumption of a Liquid-Cooled Multicylinder Aircraft Engine as Affected by Compression Ratio and Engine Operating Conditions

    Science.gov (United States)

    Brun, Rinaldo J.; Feder, Melvin S.; Harries, Myron L.

    1947-01-01

    An investigation was conducted on a 12-cylinder V-type liquid-cooled aircraft engine of 1710-cubic-inch displacement to determine the minimum specific fuel consumption at constant cruising engine speed and compression ratios of 6.65, 7.93, and 9.68. At each compression ratio, the effect.of the following variables was investigated at manifold pressures of 28, 34, 40, and 50 inches of mercury absolute: temperature of the inlet-air to the auxiliary-stage supercharger, fuel-air ratio, and spark advance. Standard sea-level atmospheric pressure was maintained at the auxiliary-stage supercharger inlet and the exhaust pressure was atmospheric. Advancing the spark timing from 34 deg and 28 deg B.T.C. (exhaust and intake, respectively) to 42 deg and 36 deg B.T.C. at a compression ratio of 6.65 resulted in a decrease of approximately 3 percent in brake specific fuel consumption. Further decreases in brake specific fuel consumption of 10.5 to 14.1 percent (depending on power level) were observed as the compression ratio was increased from 6.65 to 9.68, maintaining at each compression ratio the spark advance required for maximum torque at a fuel-air ratio of 0.06. This increase in compression ratio with a power output of 0.585 horsepower per cubic inch required a change from . a fuel- lend of 6-percent triptane with 94-percent 68--R fuel at a compression ratio of 6.65 to a fuel blend of 58-percent, triptane with 42-percent 28-R fuel at a compression ratio of 9.68 to provide for knock-free engine operation. As an aid in the evaluation of engine mechanical endurance, peak cylinder pressures were measured on a single-cylinder engine at several operating conditions. Peak cylinder pressures of 1900 pounds per square inch can be expected at a compression ratio of 9.68 and an indicated mean effective pressure of 320 pounds per square inch. The engine durability was considerably reduced at these conditions.

  8. Flow-Induced Vibration Measurement of an Inner Cladding Tube in a Simulated Dual-Cooled Fuel Rod

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Hee; Kim, Hyung Kyu; Yoon, Kyung Ho; Lee, Young Ho; Kim, Jae Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-05-15

    To create an internal coolant flow passage in a dual cooled fuel rod, an inner cladding tube cannot have intermediate supports enough to relieve its vibration. Thus it can be suffered from a flow-induced vibration (FIV) more severely than an outer cladding tube which will be supported by series of spacer grids. It may cause a fatigue failure at welding joints on the cladding's end plug or fluid elastic instability of long, slender inner cladding due to decrease of a critical flow velocity. This is one of the challenging technical issues when a dual cooled fuel assembly is to be realized into a conventional reactor core To study an actual vibration phenomenon of a dual cooled fuel rod, FIV tests using a small-scale test bundle are being carried out. Measurement results of inner cladding tube of two typically simulated rods are presented. Causes of the differences in the vibration amplitude and response spectrum of the inner cladding tube in terms of intermediate support condition and pellet stacking are discussed.

  9. Physicochemical characterization of particulate emissions from a compression ignition engine employing two injection technologies and three fuels.

    Science.gov (United States)

    Surawski, N C; Miljevic, B; Ayoko, G A; Roberts, B A; Elbagir, S; Fairfull-Smith, K E; Bottle, S E; Ristovski, Z D

    2011-07-01

    Alternative fuels and injection technologies are a necessary component of particulate emission reduction strategies for compression ignition engines. Consequently, this study undertakes a physicochemical characterization of diesel particulate matter (DPM) for engines equipped with alternative injection technologies (direct injection and common rail) and alternative fuels (ultra low sulfur diesel, a 20% biodiesel blend, and a synthetic diesel). Particle physical properties were addressed by measuring particle number size distributions, and particle chemical properties were addressed by measuring polycyclic aromatic hydrocarbons (PAHs) and reactive oxygen species (ROS). Particle volatility was determined by passing the polydisperse size distribution through a thermodenuder set to 300 °C. The results from this study, conducted over a four point test cycle, showed that both fuel type and injection technology have an impact on particle emissions, but injection technology was the more important factor. Significant particle number emission (54%-84%) reductions were achieved at half load operation (1% increase-43% decrease at full load) with the common rail injection system; however, the particles had a significantly higher PAH fraction (by a factor of 2 to 4) and ROS concentrations (by a factor of 6 to 16) both expressed on a test-cycle averaged basis. The results of this study have significant implications for the health effects of DPM emissions from both direct injection and common rail engines utilizing various alternative fuels.

  10. Compressed natural gas (CNG) in fueled systems and the significance of CNG in vehicular transportation

    Energy Technology Data Exchange (ETDEWEB)

    Ayar, G. [Besikduzu, Trabzon (Turkey)

    2006-05-15

    Most NG vehicles operate using compressed natural gas (CNG). CNG's popularity stems, in part, from its clean-burning properties. In addition, more than 85,000 CNG vehicles, including one out of every five transit buses, are operating successfully today. This compressed gas is stored in similar fashion to a car's gasoline tank, attached to the rear, top, or undercarriage of the vehicle in a tube-shaped storage tank. A CNG tank can be filled in a similar manner, and in a similar amount of time, to a gasoline tank. (author)

  11. A study of diesel-hydrogen fuel exhaust emissions in a compression ignition engine/generator assembly

    International Nuclear Information System (INIS)

    Karri, V.; Hafez, H.A.; Kirkegaard, J.F.

    2006-01-01

    A compression engine and duel-fuel supply system was studied in order to determine the influence of hydrogen gas on a diesel engine's exhaust system. Commercially available solenoid valves and pulse actuators were used in a customized mechatronic control unit (MICU) to inject the hydrogen gas into the cylinders during the experiments. The MICU was designed as a generic external attachment. Diesel fuel was used to ignite the hydrogen gas-air mixture after compression. Various different electrical loads were then applied using an alternator in order to stimulate the engine governor and control diesel flow. Results of the study showed that measured carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO x ) loads of exhaust emissions increased, while emissions of carbon dioxide (CO 2 ) decreased. Results also showed that higher temperatures and levels of NO x occurred when hydrogen was mixed with the induced air. It was concluded that higher levels of hydrogen may be needed to reduce emissions. 17 refs., 5 tabs., 2 figs

  12. Prediction of an optimum biodiesel-diesel blended fuel for compression ignition engine using GT-power

    International Nuclear Information System (INIS)

    Shah, A.N.; Shah, F.H.; Shahid, E.M.; Gardezi, S.A.R.

    2014-01-01

    This paper describes the development of a turbocharged direct-injection compression ignition (CI) engine model using fluid-dynamic engine simulation codes through a simulating tool known as GT Power. The model was first fueled with diesel, and then with various blends of biodiesel and diesel by allotting suitable parameters to predict an optimum blended fuel. During the optimization, main focus was on the engine performance, combustion, and one of the major regulated gaseous pollutants known as oxides of nitrogen (NOx). The combustion parameters such as Premix Duration (DP), Main Duration (DM), Premix Fraction (FP), Main Exponent (EM) and ignition delay (ID) affect the start of injection (SOI) angle, and thus played significant role in the prediction of optimum blended fuel. The SOI angle ranging from 5.2 to 5.7 degree crank angle (DCA) measured before top dead center (TDC) revealed an optimum biodiesel-diesel blend known as B20 (20% biodiesel and 80% diesel by volume). B20 exhibited the minimum possible NOx emissions, better combustion and acceptable engine performance. Moreover, experiments were performed to validate the simulated results by fueling the engine with B20 fuel and operating it on AC electrical dynamometer. Both the experimental and simulated results were in good agreement revealing maximum deviations of only 3%, 3.4%, 4.2%, and 5.1% for NOx, maximum combustion pressure (MCP), engine brake power (BP), and brake specific fuel consumption (BSFC), respectively. Meanwhile, a positive correlation was found between MCP and NOx showing that both the parameters are higher at lower speeds, relative to higher engine speeds. (author)

  13. Gasoline – ignition improver – oxygenate blends as fuels for advanced compression ignition combustion

    NARCIS (Netherlands)

    Zhou, L.; Boot, M.D.; Goey, de L.P.H.

    2013-01-01

    Mixing is inhibited both by the relatively low volatility of conventional diesel fuel and the short premixing time due to high fuel reactivity (i.e. cetane number (CN)). Consequently, in this research two promising oxygenates which can be produced from 2 nd generation biomass -ethanol from cellulose

  14. Durability Testing of Biomass Based Oxygenated Fuel Components in a Compression Ignition Engine

    Energy Technology Data Exchange (ETDEWEB)

    Ratcliff, Matthew A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); McCormick, Robert L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Baumgardner, Marc E. [Gonzaga University; Lakshminarayanan, Arunachalam [Colorado State University; Olsen, Daniel B. [Colorado State University; Marchese, Anthony J. [Colorado State University

    2017-10-18

    Blending cellulosic biofuels with traditional petroleum-derived fuels results in transportation fuels with reduced carbon footprints. Many cellulosic fuels rely on processing methods that produce mixtures of oxygenates which must be upgraded before blending with traditional fuels. Complete oxygenate removal is energy-intensive and it is likely that such biofuel blends will necessarily contain some oxygen content to be economically viable. Previous work by our group indicated that diesel fuel blends with low levels (<4%-vol) of oxygenates resulted in minimal negative effects on short-term engine performance and emissions. However, little is known about the long-term effects of these compounds on engine durability issues such as the impact on fuel injection, in-cylinder carbon buildup, and engine oil degradation. In this study, four of the oxygenated components previously tested were blended at 4%-vol in diesel fuel and tested with a durability protocol devised for this work consisting of 200 hrs of testing in a stationary, single-cylinder, Yanmar diesel engine operating at constant load. Oil samples, injector spray patterns, and carbon buildup from the injector and cylinder surfaces were analyzed. It was found that, at the levels tested, these fuels had minimal impact on the overall engine operation, which is consistent with our previous findings.

  15. Impact of Fire Resistant Fuel Blends on Compression Ignition Engine Performance

    Science.gov (United States)

    2011-07-01

    exhaust backpressure .  Emissions are sampled from an exhaust probe installed between the engine and exhaust system butterfly valve.  Crankcase...1  3.0  EFFECTS ON ENGINE PERFORMANCE...fuel as it is heated, effectively limiting oxygen available to combust with the fuel. The research program ended in 1987 without the FRF blend

  16. The co-evolution of alternative fuel infrastructure and vehicles. A study of the experience of Argentina with compressed natural gas

    International Nuclear Information System (INIS)

    Collantes, Gustavo; Melaina, Marc W.

    2011-01-01

    In a quest for strategic and environmental benefits, the developed countries have been trying for many years to increase the share of alternative fuels in their transportation fuel mixes. They have met very little success though. In this paper, we examine the experience of Argentina with compressed natural gas. We conducted interviews with a wide range of stakeholders and analyzed econometrically data collected in Argentina to investigate the factors, economic, political, and others that determined the high rate of adoption of this fuel. A central objective of this research was to identify lessons that could be useful to developed countries in their efforts to deploy alternative fuel vehicles. We find that fuel price regulation was a significant determinant of the adoption of compressed natural gas, while, contrary to expectations, government financing of refueling infrastructure was minimal. (author)

  17. Economic evaluation of dual purpose desalination plants by fuel type in Korea

    International Nuclear Information System (INIS)

    Seung-Su, Kim; Man-Ki, Lee

    2007-01-01

    In light of the recent rapid increase in the fossil fuel prices it is meaningful to evaluate the impact of these price changes in the economics of dual-purpose desalination projects producing electricity and fresh water simultaneously. The price of crude oil and LNG (Liquefied Natural Gas) has increased by about 200% and 100% during the past three or four years. The uranium price has also increased by nearly 500% during the same period. The purpose of this paper is to analyze and compare the economics of SMART (System-integrated Modular Advanced ReacTor) which is being developed as a small size PWR type and the LNG Combine Cycle coupled with MED (Multi-Effect Distillation) which are being acknowledged as promising energy sources for the future in Korea. The methods of analysis used in this paper are the lifetime leveled cost method for the power and water cost calculation and the power credit method for the total cost allocation. DEEP (Devaluation Economic Evaluation Program) developed by IAEA was used to perform an economic comparison between the two dual-purpose desalination projects. From the results of the analysis it is found that the desalination by SMART-MED is much superior to that of LNG CC-MED under the current economic and technical situations. It is also shown that the relative superiority of SMART-MED to LNG CC-MED will be maintained even in case where an increase in the uranium price and the SMART construction cost would reach a maximum in the sensitivity analysis. In the case that the discount rate declines to 5% per year, the relative attractiveness of SMART-MED which is a capital intensive plant will be enhanced when compared to that for a 7% discount rate. In addition to this, it is thought that a nuclear energy source will be favored much more than now in the field of desalination if the regulations for the emission of greenhouse gases are to be strengthened. (authors)

  18. Knock-Limited Performance of Triptane and 28-R Fuel Blends as Affected by Changes in Compression Ratio and in Engine Operating Variables

    Science.gov (United States)

    Brun, Rinaldo J.; Feder, Melvin S.; Fisher, William F.

    1947-01-01

    A knock-limited performance investigation was conducted on blends of triptane and 28-P fuel with a 12-cylinder, V-type, liquid-cooled aircraft engine of 1710-cubic-inch displacement at three compression ratios: 6.65, 7.93, and 9.68. At each compression ratio, the effect of changes in temperature of the inlet air to the auxiliary-stage supercharger and in fuel-air ratio were investigated at engine speeds of 2280 and. 3000 rpm. The results show that knock-limited engine performance, as improved by the use of triptane, allowed operation at both take-off and cruising power at a compression ratio of 9.68. At an inlet-air temperature of 60 deg F, an engine speed of 3000 rpm ; and a fuel-air ratio of 0,095 (approximately take-off conditions), a knock-limited engine output of 1500 brake horsepower was possible with 100-percent 28-R fuel at a compression ratio of 6.65; 20-percent triptane was required for the same power output at a compression ratio of 7.93, and 75 percent at a compression ratio of 9.68 allowed an output of 1480 brake horsepower. Knock-limited power output was more sensitive to changes in fuel-air ratio as the engine speed was increased from 2280 to 3000 rpm, as the compression ratio is raised from 6.65 to 9.68, or as the inlet-air temperature is raised from 0 deg to 120 deg F.

  19. Effects of diesel/ethanol dual fuel on emission characteristics in a heavy-duty diesel engine

    Science.gov (United States)

    Liu, Junheng; Sun, Ping; Zhang, Buyun

    2017-09-01

    In order to reduce emissions and diesel consumption, the gas emissions characteris-tics of diesel/aqueous ethanol dual fuel combustion (DFC) were carried out on a heavy-duty turbocharged and intercooled automotive diesel engine. The aqueous ethanol is prepared by a blend of anhydrous ethanol and water in certain volume proportion. In DFC mode, aqueous ethanol is injected into intake port to form homogeneous charge, and then ignited by the diesel fuel. Results show that DFC can reduce NOx emissions but increase HC and CO emissions, and this trend becomes more prominent with the increase of water blending ratio. Increased emissions of HC and CO could be efficiently cleaned by diesel oxidation catalytic converter (DOC), even better than those of diesel fuel. It is also found that DFC mode reduces smoke remarkably, while increases some unconventional emissions such as formaldehyde and acetal-dehyde. However, unconventional emissions could be reduced approximately to the level of baseline engine with a DOC.

  20. Ozone applied to the homogeneous charge compression ignition engine to control alcohol fuels combustion

    International Nuclear Information System (INIS)

    Masurier, J.-B.; Foucher, F.; Dayma, G.; Dagaut, P.

    2015-01-01

    Highlights: • Ozone was useful to control combustion phasing of alcohol fuels in HCCI engine. • Ozone helps to improve the combustion and advance its phasing. • Butanol is more impacted by ozone than methanol and ethanol. • HCCI combustion parameters may be controlled by managing ozone concentration. • Kinetics demonstrates that alcohol fuels are initially oxidized by O-atoms. - Abstract: The present investigation examines the impact of seeding the intake of an HCCI engine with ozone, one of the most oxidizing chemical species, on the combustion of three alcohol fuels: methanol, ethanol and n-butanol. The research was performed through engine experiments and constant volume computations. The results showed that increasing the ozone concentration led to an improvement in combustion coupled with a combustion advance. It was also observed, by comparing the results for each fuel selected, that n-butanol is the most impacted by ozone seeding and methanol the least. Further analyses of the experimental results showed that the alcohol fuel combustion can be controlled with ozone, which presents an interesting potential. Finally, computation results confirmed the experimental results observed. They also showed that in presence of ozone, alcohol fuels are not initially oxidized by molecular oxygen but by O-atoms coming from the ozone decomposition.

  1. Development of dual-purpose metal cask for interim storage of spent nuclear fuel (1). Outline of cask structure

    International Nuclear Information System (INIS)

    Shimizu, Masashi; Hayashi, Makoto; Kashiwakura, Jun

    2003-01-01

    Spent fuels discharged from nuclear power plants in Japan are planed to be reprocessed at the nuclear fuel recycle plant under construction at Rokkasho-mura. Since the amount of the spent fuels exceeds that of recycled fuel, the spent fuels have to be properly stored and maintained as recycle fuel resource until the beginning of the reprocessing. For that sake, interim storage installations are being constructed outside the nuclear power plants by 2010. The storage dry casks have been practically used as the interim storage in the nuclear power plants. From this reason, the storage system using the storage dry casks is promising as the interim storage installations away form the reactors, which are under discussion. In the interim storage facilities, the storage using the dry cask of the storage metal cask with business showings, having the function of transportation is now under discussion. By employing transportation and storage dual-purpose cask, the repack equipments can be exhausted, and the reliability of the interim storage installations can be increased. Hitachi, Ltd. has been developing the high reliable and economical transportation and storage dry metal cask. In this report, the outline of our developing transportation and storage dry cask is described. (author)

  2. An experimental investigation on engine performance and emissions of a supercharged H{sub 2}-diesel dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Murari Mohon [Rajshahi University of Engineering and Technology (JSPS Research Fellow, Okayama University), Tsushima-Naka 3, Okayama 700-8530 (Japan); Department of Mechanical Engineering, Okayama University, Tsushima-Naka 3, Okayama 700-8530 (Japan); Tomita, Eiji; Kawahara, Nobuyuki; Harada, Yuji [Department of Mechanical Engineering, Okayama University, Tsushima-Naka 3, Okayama 700-8530 (Japan); Sakane, Atsushi [Mitsui Engineering and Shipbuilding Co. Ltd., 6-4 Tsukiji 5-chome, Chuo-ku, Tokyo (Japan)

    2010-01-15

    This study investigated the engine performance and emissions of a supercharged engine fueled by hydrogen and ignited by a pilot amount of diesel fuel in dual-fuel mode. The engine was tested for use as a cogeneration engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant pilot injection pressure and pilot quantity for different fuel-air equivalence ratios and at various injection timings without and with charge dilution. The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. The engine was tested first with hydrogen-operation condition up to the maximum possible fuel-air equivalence ratio of 0.3. A maximum IMEP of 908 kPa and a thermal efficiency of about 42% were obtained. Equivalence ratio could not be further increased due to knocking of the engine. The emission of CO was only about 5 ppm, and that of HC was about 15 ppm. However, the NOx emissions were high, 100-200 ppm or more. The charge dilution by N{sub 2} was then performed to obtain lower NOx emissions. The 100% reduction of NOx was achieved. Due to the dilution by N{sub 2} gas, higher amount of energy could be supplied from hydrogen without knocking, and about 13% higher IMEP was produced than without charge dilution. (author)

  3. Transformation of a car diesel engine with direct injection and common rail into a dual fuel engine; Trasformazione di un motore automobilistico diesel ad iniezione diretta dotato di common rail in un motore dual fuel

    Energy Technology Data Exchange (ETDEWEB)

    De Risi, A.; Laforgia, D. [Lecce Univ. (Italy). Dipt. di Scienza dei Materiali

    1999-08-01

    The reduced polluting emissions make natural gas a quite interesting alternative fuel for automotive applications. Therefore a car diesel engine has been transformed into a dual fuel engine with pilot injection via the common rail injection system used to ignite the methane-air charge. Standard injection pumps show a certain instability at low flow rates and high engine speed. On the opposite the new common rail system allows to ignite the fuel in all conditions with an amount of gas oil less than 8% of the entire energy required by the engine was enough to ignite the fuel. Furthermore, a power increase has been obtained, with an overall efficiency equal to or even higher than a conventional engine. The article deals with a series of test carried out on 1929 cm{sup 3} direct injection turbo-charged engine and presents the preliminary results. [Italian] La riduzione delle emissioni inquinanti rende il metano un combustibile alternativo piuttosto interessante per applicazioni automobilistiche. Per quasta ragione e' stata realizzata la trasformazione di un motore automobilitico diesel ad iniezione diretta in un motore dual fuel con iniezione pilota prodotta da un sistema common rail. L'adozione del sistema common rail consente l'accensione in ogni condizione con una quantita' di combustibile inferiore all'8% dell'intera energia richiesta alla potenza nominale del motore risolvendo i problemi di instabilita' che una pompa normale presenta a basse portate e ad alta velocita'. In alcuni casi e' stato sufficiente il 3% dell'energia totale richiesta dal motore per accendere la carica. Inoltre si e' ottenuto un aumento della potenza con un'efficienza globale analoga a qualla del motore tradizionale o addirittura migliore. Si riportano i risultati di una campagna di prove condotta su un motore sovralimentato ad iniezione diretta (1929 cm{sup 3}).

  4. Hydrogen enriched compressed natural gas (HCNG: A futuristic fuel for internal combustion engines

    Directory of Open Access Journals (Sweden)

    Nanthagopal Kasianantham

    2011-01-01

    Full Text Available Air pollution is fast becoming a serious global problem with increasing population and its subsequent demands. This has resulted in increased usage of hydrogen as fuel for internal combustion engines. Hydrogen resources are vast and it is considered as one of the most promising fuel for automotive sector. As the required hydrogen infrastructure and refueling stations are not meeting the demand, widespread introduction of hydrogen vehicles is not possible in the near future. One of the solutions for this hurdle is to blend hydrogen with methane. Such types of blends take benefit of the unique combustion properties of hydrogen and at the same time reduce the demand for pure hydrogen. Enriching natural gas with hydrogen could be a potential alternative to common hydrocarbon fuels for internal combustion engine applications. Many researchers are working on this for the last few years and work is now focused on how to use this kind of fuel to its maximum extent. This technical note is an assessment of HCNG usage in case of internal combustion engines. Several examples and their salient features have been discussed. Finally, overall effects of hydrogen addition on an engine fueled with HCNG under various conditions are illustrated. In addition, the scope and challenges being faced in this area of research are clearly described.

  5. An insight on hydrogen fuel injection techniques with SCR system for NO{sub X} reduction in a hydrogen-diesel dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Saravanan, N. [ERC Engines, Hall 11A, Tata Motors, Pimpri, Pune 411019, Maharashtra (India); Nagarajan, G. [Department of Mechanical Engineering, ICE Division, College of Engineering, Guindy, Anna University-Chennai, Chennai 600 025 (India)

    2009-11-15

    Internal combustion engines continue to dominate in many fields like transportation, agriculture and power generation. Among the various alternative fuels, hydrogen is a long-term renewable and less polluting fuel (Produced from renewable energy sources). In the present experimental investigation, the performance and emission characteristics were studied on a direct injection diesel engine in dual fuel mode with hydrogen inducted along with air adopting carburetion, timed port and manifold injection techniques. Results showed that in timed port injection, the specific energy consumption reduces by 15% and smoke level by 18%. The brake thermal efficiency and NO{sub X} increases by 17% and 34% respectively compared to baseline diesel. The variation in performance between port and manifold injection is not significant. The unburnt hydrocarbons and carbon monoxide emissions are lesser in port injection. The oxides of nitrogen are higher in hydrogen operation (both port and manifold injection) compared to diesel engine. In order to reduce the NO{sub X} emissions, a selective catalytic converter was used in hydrogen port fuel injection. The NO{sub X} emission reduced upto a maximum of 74% for ANR (ratio of flow rate of ammonia to the flow rate of NO) of 1.1 with a marginal reduction in efficiency. Selective catalytic reduction technique has been found to be effective in reducing the NO{sub X} emission from hydrogen fueled diesel engines. (author)

  6. Application of a dual-resolution voxelization scheme to compressed-sensing (CS)-based iterative reconstruction in digital tomosynthesis (DTS)

    Science.gov (United States)

    Park, S. Y.; Kim, G. A.; Cho, H. S.; Park, C. K.; Lee, D. Y.; Lim, H. W.; Lee, H. W.; Kim, K. S.; Kang, S. Y.; Park, J. E.; Kim, W. S.; Jeon, D. H.; Je, U. K.; Woo, T. H.; Oh, J. E.

    2018-02-01

    In recent digital tomosynthesis (DTS), iterative reconstruction methods are often used owing to the potential to provide multiplanar images of superior image quality to conventional filtered-backprojection (FBP)-based methods. However, they require enormous computational cost in the iterative process, which has still been an obstacle to put them to practical use. In this work, we propose a new DTS reconstruction method incorporated with a dual-resolution voxelization scheme in attempt to overcome these difficulties, in which the voxels outside a small region-of-interest (ROI) containing target diagnosis are binned by 2 × 2 × 2 while the voxels inside the ROI remain unbinned. We considered a compressed-sensing (CS)-based iterative algorithm with a dual-constraint strategy for more accurate DTS reconstruction. We implemented the proposed algorithm and performed a systematic simulation and experiment to demonstrate its viability. Our results indicate that the proposed method seems to be effective for reducing computational cost considerably in iterative DTS reconstruction, keeping the image quality inside the ROI not much degraded. A binning size of 2 × 2 × 2 required only about 31.9% computational memory and about 2.6% reconstruction time, compared to those for no binning case. The reconstruction quality was evaluated in terms of the root-mean-square error (RMSE), the contrast-to-noise ratio (CNR), and the universal-quality index (UQI).

  7. Experimental study on two-stage compression refrigeration/heat pump system with dual-cylinder rolling piston compressor

    International Nuclear Information System (INIS)

    Shuxue, Xu; Guoyuan, Ma

    2014-01-01

    A thermodynamically analytical model on the two-stage compression refrigeration/heat pump system with vapor injection was derived. The optimal volume ratio of the high-pressure cylinder to the low-pressure one has been discussed under both cooling and heating conditions. Based on the above research, the prototype was developed and its experimental setup established. A comprehensive experiments for the prototype have been conducted, and the results show that, compared with the single-stage compression heat pump system, the cooling capacity and cooling COP can increase 5%–15% and 10–12%, respectively. Also, the heating capacity with the evaporating temperature ranging from 0.3 to 3 °C is 92–95% of that under the rate condition with the evaporating temperature of 7 °C, and 58% when the evaporation temperature is between −28 °C and −24 °C. -- Highlights: • The volume ratio of the compressor is between 0.65 and 0.78 and the relative vapor injection mass ranges from 15% to 20%. • The cooling capacity and COP of the two-stage compression system can improve 5%–15% and 10%–12%. • The heating capacity can also be improved under low temperature condition

  8. Exploration of waste cooking oil methyl esters (WCOME as fuel in compression ignition engines: A critical review

    Directory of Open Access Journals (Sweden)

    S. Kathirvel

    2016-06-01

    Full Text Available The ever growing human population and the corresponding economic development of mankind have caused a relentless surge in the energy demand of the world. The fast diminishing fossil fuel reserves and the overdependence of petroleum based fuels have already prompted the world to look for alternate sources of energy to offset the fuel crisis in the future. Waste Cooking Oil Methyl Ester (WCOME has proven itself as a viable alternate fuel that can be used in Compression Ignition (CI engines due to its low cost, non-toxicity, biodegradability and renewable nature. It also contributes a minimum amount of net greenhouse gases, such as CO2, SO2 and NO emissions to the atmosphere. The main objective of this paper is to focus on the study of the performance, combustion and emission parameters of CI engines using WCOME and to explore the possibility of utilizing WCOME blends with diesel extensively in place of diesel. The production methods used for transesterification play a vital role in the physiochemical properties of the methyl esters produced. Various production intensification technologies such as hydrodynamic cavitation and ultrasonic cavitation were employed to improve the yield of the methyl esters during transesterification. This review includes the study of WCOME from different origins in various types of diesel engines. Most of the studies comply with the decrease in carbon monoxide (CO emissions and the increase in brake thermal efficiency while using WCOME in CI engines. Many researchers reported slight increase in the emissions of oxides of nitrogen. ANN modeling has been widely used to predict the process variables of the diesel engine while using WCOME. The versatility of ANN modeling was proven by the minimum error percentages of the actual and predicted values of the performance and emission characteristics.

  9. Design and neutronic investigation of the Nano fluids application to VVER-1000 nuclear reactor with dual cooled annular fuel

    International Nuclear Information System (INIS)

    Ansarifar, G.R.; Ebrahimian, M.

    2016-01-01

    Highlights: • The change in neutronic parameters to the use of nanofluid as coolant is presented. • Nanoparticle deposition on fuel clad is investigated. • Radial and axial local power peaking factors are presented. • ZrO 2 and Al 2 O 3 have the lowest rate of K eff drop off. - Abstract: Nowadays, many efforts have been made to improve the efficiency of nuclear power plants. One of which is use of the dual cooled annular fuel which is an internally and externally cooled annular fuel with many advantages in heat transfer characteristics. Another is the use of nanoparticle/water (nanofluid) as coolant. In this paper, by combining these two methods, the change in neutronic parameters of the VVER-1000 nuclear reactor core with dual cooled annular fuel attributable to the use of nanoparticle/water (nanofluid) as coolant is presented. Optimization of type and volume fraction of nanoparticles in water that affect the safety enhancement of core primary parameters is intended in this study. Reactivity change, radial and axial local power peaking factors (LPPF), and the consequence of nanoparticle deposition on fuel clad are investigated. As a result of changing the effective multiplication factor and PPF calculations for six types of nanoparticles which have been studied extensively for their heat transfer properties including Alumina, Aluminum, Copper oxide, Copper, Titania, and Zirconia with different volume fractions, it can be concluded that at low concentration (0.03 volume fraction), Zirconia and Alumina are the optimum nanoparticles for normal operation. The maximum radial and axial PPF are found to be invariant to the type of nanofluid at low volume fractions. With an increase in nanoparticle deposition thickness on the outer and inner clad, a flux and K eff depression occurred and ZrO 2 and Al 2 O 3 have the lowest rate of drop off.

  10. Emission and operating performance of a biomethane tractor with dual fuel engine; Emissions- und Betriebsverhalten eines Biomethan-Traktors mit Zuendstrahlmotor

    Energy Technology Data Exchange (ETDEWEB)

    Mautner, Sebastian [Technologie- und Foerderzentrum (TFZ), Straubing (Germany); Emberger, Peter; Thuneke, Klaus; Remmele, Edgar

    2016-08-01

    The use of biomethane as fuel for agricultural machinery with dual fuel technology is contributing to climate protection and ensures safe fuel supply. So far, hardly any documented operational experiences are known. The aim of the project, funded by the Bavarian Ministry of Economic Affairs and Media, Energy and Technology, was to investigate practicability for daily use and the emission behaviour of a Valtra N101 prototype tractor (exhaust stage IIIA). The retrofitted dual-fuel technology of the former conventional diesel tractor simultaneously uses biomethane or natural gas and diesel as ignition fuel. During the field test over 590 working hours, the tractor showed overall high reliability. On average the operating range in dual-fuel mode with one complete filling of the gas tanks was about 11.5 hours. On the tractor test bench a significant improvement of the exhaust emissions could be observed, since the gas ECU had been optimized and changed by the manufacturer. For dual-fuel operation, nitrogen oxides (NO{sub x}) are lower, whereas carbon monoxide (CO), hydrocarbons (HC) and particulate matter emissions (PM) are higher compared to solely diesel operation. In particular, HC emissions exceed the proposed limiting value, submitted by the European Commission. This is due to incomplete gas combustion and insufficient conversion by the exhaust after-treatment-system (methane slip). A big potential for optimization is expected by adjusting the operating point-specific gasdiesel ratio and improving the exhaust gas aftertreatment system.

  11. Thermal design of a natural gas - diesel dual fuel turbocharged V18 engine for ship propulsion and power plant applications

    Science.gov (United States)

    Douvartzides, S.; Karmalis, I.

    2016-11-01

    A detailed method is presented on the thermal design of a natural gas - diesel dual fuel internal combustion engine. An 18 cylinder four stroke turbocharged engine is considered to operate at a maximum speed of 500 rpm for marine and power plant applications. Thermodynamic, heat transfer and fluid flow phenomena are mathematically analyzed to provide a real cycle analysis together with a complete set of calculated operation conditions, power characteristics and engine efficiencies. The method is found to provide results in close agreement to published data for the actual performance of similar engines such as V18 MAN 51/60DF.

  12. Experimental investigation of homogeneous charge compression ignition combustion of biodiesel fuel with external mixture formation in a CI engine.

    Science.gov (United States)

    Ganesh, D; Nagarajan, G; Ganesan, S

    2014-01-01

    In parallel to the interest in renewable fuels, there has also been increased interest in homogeneous charge compression ignition (HCCI) combustion. HCCI engines are being actively developed because they have the potential to be highly efficient and to produce low emissions. Even though HCCI has been researched extensively, few challenges still exist. These include controlling the combustion at higher loads and the formation of a homogeneous mixture. To obtain better homogeneity, in the present investigation external mixture formation method was adopted, in which the fuel vaporiser was used to achieve excellent HCCI combustion in a single cylinder air-cooled direct injection diesel engine. In continuation of our previous works, in the current study a vaporised jatropha methyl ester (JME) was mixed with air to form a homogeneous mixture and inducted into the cylinder during the intake stroke to analyze the combustion, emission and performance characteristics. To control the early ignition of JME vapor-air mixture, cooled (30 °C) Exhaust gas recirculation (EGR) technique was adopted. The experimental result shows 81% reduction in NOx and 72% reduction in smoke emission.

  13. Certain investigation in a compression ignition engine using rice bran methyl ester fuel blends with ethanol additive

    Directory of Open Access Journals (Sweden)

    Krishnan Arumugam

    2017-01-01

    Full Text Available In this study and analysis, the physical properties such as calorific value, viscosity, flash, and fire point temperatures of rice bran oil methyl ester were found. The rice bran oil biodiesel has been prepared by transesterification process from pure rice bran oil in the presence of methanol and NaOH. Moreover, property enhancement of rice bran oil methyl ester was also made by adding different additives such as ethanol in various proportions. Rice bran oil methyl ester with 1, 3, and 5% ethanol were analyzed for its fuel properties. The effects of diesel-B20ROME blends with ethanol additive of 1, 3, and 5% on a compression ignition engine were examined considering its emissions. It is found that the increase in biodiesel concentration in the fuel blend influences CO2 and NOx emissions. On the other hand CO and HC emissions are reduced. It is interesting to observe the emission as ethanol-B20ROME blends, reduces CO2 and NOx which are the major contributors to global warming. As the NOx and CO2 can be reduced drastically by the proposed blends, the global warming can be reduced considerably.

  14. Potential utilization of biodiesel as alternative fuel for compression ignition engine in Malaysia

    Science.gov (United States)

    Wahab, M. A.; Ma'arof, M. I. N.; Ahmad, I. N.; Husain, H.

    2017-10-01

    Biodiesel is a type of fuel which is derived from various sources of vegetable plants and waste fuels. Today, numerous biodiesels have been engineered to be at par or even better in term of performance in comparison to pure diesel. Therefore, biodiesel has shown a promising sign as one of the best candidate in overcoming total dependency on pure diesel. This paper gives review on various tests and experiments conducted on biodiesel in order to highlight the potentials given by this particular fuel. In addition, providing the supporting evidences to further endorse for a mass usage of biodiesel in Malaysia - simultaneously, driving the country to become a potential global biodiesel producer in the near future. The reviewed studies were obtained mainly via indexed journals and online libraries. Conclusively, every test and study for every blend of biodiesel had shown consistent positive results in regards to performance and in overcoming emission related issues. Thus, providing the evidence that biodiesel is highly reliable. Malaysia as a semi-agricultural nation could take the advantage in becoming one of the leading global biodiesel producers. Nevertheless, this will requires total cooperation of every concerned government bodies and authorities.

  15. Fuel cell plates with skewed process channels for uniform distribution of stack compression load

    Science.gov (United States)

    Granata, Jr., Samuel J.; Woodle, Boyd M.

    1989-01-01

    An electrochemical fuel cell includes an anode electrode, a cathode electrode, an electrolyte matrix sandwiched between electrodes, and a pair of plates above and below the electrodes. The plate above the electrodes has a lower surface with a first group of process gas flow channels formed thereon and the plate below the electrodes has an upper surface with a second group of process gas flow channels formed thereon. The channels of each group extend generally parallel to one another. The improvement comprises the process gas flow channels on the lower surface of the plate above the anode electrode and the process gas flow channels on the upper surface of the plate below the cathode electrode being skewed in opposite directions such that contact areas of the surfaces of the plates through the electrodes are formed in crisscross arrangements. Also, the plates have at least one groove in areas of the surfaces thereof where the channels are absent for holding process gas and increasing electrochemical activity of the fuel cell. The groove in each plate surface intersects with the process channels therein. Also, the opposite surfaces of a bipolar plate for a fuel cell contain first and second arrangements of process gas flow channels in the respective surfaces which are skewed the same amount in opposite directions relative to the longitudinal centerline of the plate.

  16. 26 CFR 48.4041-7 - Dual use of taxable liquid fuel.

    Science.gov (United States)

    2010-04-01

    ... taxable liquid fuel. Tax applies to all taxable liquid fuel sold for use or used as a fuel in the motor which is used to propel a diesel-powered vehicle or in the motor used to propel a motor vehicle... vehicle, motorboat, or aircraft. Thus, if the motor of a diesel-powered highway vehicle or a motorboat...

  17. Performance enhancement of polymer electrolyte membrane fuel cells by dual-layered membrane electrode assembly structures with carbon nanotubes.

    Science.gov (United States)

    Jung, Dong-Won; Kim, Jun-Ho; Kim, Se-Hoon; Kim, Jun-Bom; Oh, Eun-Suok

    2013-05-01

    The effect of dual-layered membrane electrode assemblies (d-MEAs) on the performance of a polymer electrolyte membrane fuel cell (PEMFC) was investigated using the following characterization techniques: single cell performance test, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV). It has been shown that the PEMFC with d-MEAs has better cell performance than that with typical mono-layered MEAs (m-MEAs). In particular, the d-MEA whose inner layer is composed of multi-walled carbon nanotubes (MWCNTs) showed the best fuel cell performance. This is due to the fact that the d-MEAs with MWCNTs have the highest electrochemical surface area and the lowest activation polarization, as observed from the CV and EIS test.

  18. Generator gas as a fuel to power a diesel engine

    Directory of Open Access Journals (Sweden)

    Tutak Wojciech

    2014-01-01

    Full Text Available The results of gasification process of dried sewage sludge and use of generator gas as a fuel for dual fuel turbocharged compression ignition engine are presented. The results of gasifying showed that during gasification of sewage sludge is possible to obtain generator gas of a calorific value in the range of 2.15  2.59 MJ/m3. It turned out that the generator gas can be effectively used as a fuel to the compression ignition engine. Because of gas composition, it was possible to run engine with partload conditions. In dual fuel operation the high value of indicated efficiency was achieved equal to 35%, so better than the efficiency of 30% attainable when being fed with 100% liquid fuel. The dual fuel engine version developed within the project can be recommended to be used in practice in a dried sewage sludge gasification plant as a dual fuel engine driving the electric generator loaded with the active electric power limited to 40 kW (which accounts for approx. 50% of its rated power, because it is at this power that the optimal conditions of operation of an engine dual fuel powered by liquid fuel and generator gas are achieved. An additional advantage is the utilization of waste generated in the wastewater treatment plant.

  19. Thermodynamic Analyses of Biomass Gasification Integrated Externally Fired, Post-Firing and Dual-Fuel Combined Cycles

    Directory of Open Access Journals (Sweden)

    Saeed Soltani

    2015-01-01

    Full Text Available In the present work, the results are reported of the energy and exergy analyses of three biomass-related processes for electricity generation: the biomass gasification integrated externally fired combined cycle, the biomass gasification integrated dual-fuel combined cycle, and the biomass gasification integrated post-firing combined cycle. The energy efficiency for the biomass gasification integrated post-firing combined cycle is 3% to 6% points higher than for the other cycles. Although the efficiency of the externally fired biomass combined cycle is the lowest, it has an advantage in that it only uses biomass. The energy and exergy efficiencies are maximized for the three configurations at particular values of compressor pressure ratios, and increase with gas turbine inlet temperature. As pressure ratio increases, the mass of air per mass of steam decreases for the biomass gasification integrated post-firing combined cycle, but the pressure ratio has little influence on the ratio of mass of air per mass of steam for the other cycles. The gas turbine exergy efficiency is the highest for the three configurations. The combustion chamber for the dual-fuel cycle exhibits the highest exergy efficiency and that for the post-firing cycle the lowest. Another benefit of the biomass gasification integrated externally fired combined cycle is that it exhibits the highest air preheater and heat recovery steam generator exergy efficiencies.

  20. Ni/Ni-YSZ current collector/anode dual layer hollow fibers for micro-tubular solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kanawka, K.; Othman, M.H.D.; Droushiotis, N.; Wu, Z.; Kelsall, G.; Li, K. [Department of Chemical Engineering and Chemical Technology, Imperial College London, London SW7 2AZ (United Kingdom)

    2011-10-15

    A co-extrusion technique was employed to fabricate a novel dual layer NiO/NiO-YSZ hollow fiber (HF) precursor which was then co-sintered at 1,400 C and reduced at 700 C to form, respectively, a meshed porous inner Ni current collector and outer Ni-YSZ anode layers for SOFC applications. The inner thin and highly porous ''mesh-like'' pure Ni layer of approximately 50 {mu}m in thickness functions as a current collector in micro-tubular solid oxide fuel cell (SOFC), aiming at highly efficient current collection with low fuel diffusion resistance, while the thicker outer Ni-YSZ layer of 260 {mu}m acts as an anode, providing also major mechanical strength to the dual-layer HF. Achieved morphology consisted of short finger-like voids originating from the inner lumen of the HF, and a sponge-like structure filling most of the Ni-YSZ anode layer, which is considered to be suitable macrostructure for anode SOFC system. The electrical conductivity of the meshed porous inner Ni layer is measured to be 77.5 x 10{sup 5} S m{sup -1}. This result is significantly higher than previous reported results on single layer Ni-YSZ HFs, which performs not only as a catalyst for the oxidation reaction, but also as a current collector. These results highlight the advantages of this novel dual-layer HF design as a new and highly efficient way of collecting current from the lumen of micro-tubular SOFC. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Effect of the use of olive–pomace oil biodiesel/diesel fuel blends in a compression ignition engine: Preliminary exergy analysis

    International Nuclear Information System (INIS)

    López, I.; Quintana, C.E.; Ruiz, J.J.; Cruz-Peragón, F.; Dorado, M.P.

    2014-01-01

    Highlights: • Olive–pomace oil (OPO) biodiesel constitute a new second-generation biofuel. • Exergy efficiency and performance of OPO biodiesel, straight and blended with diesel fuel was evaluated. • OPO biodiesel, straight and blended, provided similar performance parameters. • OPO biodiesel, straight and blended, provided similar exergy efficiency compared to diesel fuel. • OPO biodiesel, straight and blended, provided no exergy cost increment compared to diesel fuel. - Abstract: Although biodiesel is among the most studied biofuels for diesel engines, it is usually produced from edible oils, which gives way to controversy between the use of land for fuel and food. For this reason, residues like olive–pomace oil are considered alternative raw materials to produce biodiesel that do not compete with the food industry. To gain knowledge about the implications of its use, olive–pomace oil methyl ester, straight and blended with diesel fuel, was evaluated as fuel in a direct injection diesel engine Perkins AD 3-152 and compared to the use of fossil diesel fuel. Performance curves were analyzed at full load and different speed settings. To perform the exergy balance of the tested fuels, the operating conditions corresponding to maximum engine power values were considered. It was found that the tested fuels offer similar performance parameters. When straight biodiesel was used instead of diesel fuel, maximum engine power decreased to 5.6%, while fuel consumption increased up to 7%. However, taking into consideration the Second Law of the Thermodynamics, the exergy efficiency and unitary exergetic cost reached during the operation of the engine under maximum power condition for the assessed fuels do not display significant differences. Based on the exergy results, it may be concluded that olive–pomace oil biodiesel and its blends with diesel fuel may substitute the use of diesel fuel in compression ignition engines without any exergy cost increment

  2. Effect of Syngas Moisture Content on the Emissions of Micro-Gas Turbine Fueled with Syngas/LPG in Dual Fuel Mode

    Directory of Open Access Journals (Sweden)

    Sadig Hussain

    2014-07-01

    Full Text Available Syngas produced by gasification has a potential to be one of the fueling solutions for gas turbines in the future. In addition to the combustible constituents and inert gases, syngas derived by gasification contains a considerable amount of water vapor which effect on syngas combustion behaviour. In this work, a micro-gas turbine with a thermal capacity of 50 kW was simulated using ASPEN Plus. The micro gas turbine system emissions were characterized using dry syngas fuels with a different composition, syngas 1 (10.53% H2, 24.94% CO, 2.03% CH4, 12.80% CO2, and 49.70% N2 and syngas 2 (21.62% H2, 32.48% CO, 3.72% CH4, 19.69% CO2, and 22.49% N2 mixed with LPG in a dual fueling mode. The effect of syngas moisture content was then studied by testing the system with moist syngas/LPG with a moisture content ranging from 0 to 20% by volume. The study demonstrates that the syngas moisture content has high influence on nitrogen oxides and carbon monoxide emissions. It’s found that for 5% syngas moisture content, the NOx emission were reduced by 75.5% and 83% for Syngas 1 and Syngas 2 respectively. On carbon monoxide emissions and for same moisture content ratio, the reduction was found to be 43% and 57% for syngas1 and syngas 2 respectively.

  3. Feasibility of a Dual-Fuel Engine Fuelled with Waste Vegetable Oil and Municipal Organic Fraction for Power Generation in Urban Areas

    Directory of Open Access Journals (Sweden)

    L. De Simio

    2012-01-01

    Full Text Available Biomass, in form of residues and waste, can be used to produce energy with low environmental impact. It is important to use the feedstock close to the places where waste are available, and with the shortest conversion pathway, to maximize the process efficiency. In particular waste vegetable oil and the organic fraction of municipal solid waste represent a good source for fuel production in urban areas. Dual fuel engines could be taken into consideration for an efficient management of these wastes. In fact, the dual fuel technology can achieve overall efficiencies typical of diesel engines with a cleaner exhaust emission. In this paper the feasibility of a cogeneration system fuelled with waste vegetable oil and biogas is discussed and the evaluation of performance and emissions is reported on the base of experimental activities on dual fuel heavy duty engine in comparison with diesel and spark ignition engines. The ratio of biogas potential from MSW and biodiesel potential from waste vegetable oil was estimated and it results suitable for dual fuel fuelling. An electric power installation of 70 kW every 10,000 people could be achieved.

  4. Effects of diluent admissions and intake air temperature in exhaust gas recirculation on the emissions of an indirect injection dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Abd-Alla, G.H.; Soliman, H.A.; Badr, O.A.; Abd-Rabbo, M.F. [Zagazig University, Cairo (Egypt). Shoubra Faculty of Engineering

    2001-05-01

    The operation of Diesel engines on gaseous fuels, commonly known as dual fuel engines, uses Diesel fuel as the pilot fuel and gaseous fuel (methane and sometimes propane in the present work) as the main fuel. The gaseous fuel was inducted in the intake manifold to mix with the intake air. The investigation was conducted on a high speed indirect injection (Ricardo-E6) dual fuel engine and was concerned with the effects of exhaust gas recirculation (EGR) on the dual fuel engine combustion and emissions, in particular, the effects of intake air temperature and diluent admissions (N{sub 2} and CO{sub 2}) on combustion and emissions. The use of diluents to displace oxygen (O{sub 2}) in the intake air resulted in a reduction in the O{sub 2} supplied to the engine, increased the inlet charge thermal capacity (thermal effect) and, potentially, CO{sub 2} and N{sub 2} participated in the combustion process (chemical effect). In a separate series of tests, the temperature of the engine inlet charge was raised gradually in order to simulate the effect of mixing hot EGR with the engine inlet gaseous fuel air mixture. It was found that the admission of diluents resulted in reductions in the exhaust oxides of nitrogen (NO{sub x}). Higher inlet charge temperature increases the exhaust NO{sub x} but reduces the unburned hydrocarbon emissions. Finally, when carbon dioxide was added to the inlet gaseous fuel air charge, large reductions in NO{sub x} were observed. (author)

  5. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    Energy Technology Data Exchange (ETDEWEB)

    John Pratapas; Daniel Mather; Anton Kozlovsky

    2007-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen's significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an

  6. Review on the effects of dual-fuel operation, using diesel and gaseous fuels, on emissions and performance

    NARCIS (Netherlands)

    Wagemakers, A.M.L.M.; Leermakers, C.A.J.

    2012-01-01

    In recent years the automotive industry has been forced to reduce the harmful and pollutant emissions emitted by direct injected diesel engines. To accomplish this difficult task various solutions have been proposed. One of these proposed solutions is the usage of gaseous fuels in addition to the

  7. The potential of whey in driving microbial fuel cells: A dual prospect ...

    African Journals Online (AJOL)

    Renewable and green energy resources are paramount to environmental sustainability. Microbial fuel cells (MFCs) are potential candidates for these alternatives but there is need to search for cheaper fuels to drive the MFCs for realistic large scale applications. A high strength effluent such as whey, which poses a serious ...

  8. Influence of Palm Oil Fuel Ash and W/B Ratios on Compressive Strength, Water Permeability, and Chloride Resistance of Concrete

    Directory of Open Access Journals (Sweden)

    Wachilakorn Sanawung

    2017-01-01

    Full Text Available This research studies the effects of W/B ratios and palm oil fuel ash (POFA on compressive strength, water permeability, and chloride resistance of concrete. POFA was ground until the particles retained on sieve number 325 were less than 5% by weight. POFA was used to partially replace OPC at rates of 15, 25, and 35% by weight of binder. The water to binder (W/B ratios of concrete were 0.40 and 0.50. The compressive strength, water permeability, and chloride resistance of concrete were investigated up to 90 days. The results showed that POFA concrete with W/B ratio of 0.40 had the compressive strengths ranging from 45.8 to 55.9 MPa or 82–94% of OPC concrete at 90 days, while POFA concrete with W/B ratio of 0.50 had the compressive strengths of 33.9–41.9 MPa or 81–94% of OPC concrete. Furthermore, the compressive strength of concrete incorporation of ground POFA at 15% was the same as OPC concrete. The water permeability coefficient and the chloride ion penetration of POFA concrete were lower than OPC concrete when both types of concrete had the same compressive strengths. The findings also indicated that water permeability and chloride ion penetration of POFA concrete were significantly reduced compared to OPC concrete.

  9. A study on the amount of pilot injection and its effects on rich and lean boundaries of the premixed CNG/air mixture for a CNG/diesel dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Zhiqiang Lin; Wanhua Su [Tianjin University (China). State Key Laboratory of Engines

    2003-07-01

    A sequential port injection, lean-burn, fully electronically-controlled compressed natural gas (CNG)/diesel dual-fuel engine has been developed based on a turbo-charged and inter-cooled direct injection (D.I.) diesel engine. During the optimisation of engine overall performance, the effects of pilot diesel and premixed CNG/air mixture equivalence ratio on emissions (CO, HC, NO{sub x}, soot), knocking, misfire and fuel economy are studied. The rich and lean boundaries of the premixed CNG/air mixture versus engine load are also provided, considering the acceptable values of NO{sub x} and THC emissions, respectively. It is interesting to find that there is a critical amount of pilot diesel for each load and speed point, which proved to be the optimum amount of pilot fuel. Any decrease in the amount of pilot diesel from this optimum amount results in an increase of NO{sub x} emissions, because the premixed CNG/air mixture must be made richer, otherwise THC emissions would increase. However, the soot emissions remain almost unchanged at a very low level. (author)

  10. Dual-energy CT in vertebral compression fractures: performance of visual and quantitative analysis for bone marrow edema demonstration with comparison to MRI

    International Nuclear Information System (INIS)

    Bierry, Guillaume; Venkatasamy, Aina; Kremer, Stephane; Dosch, Jean-Claude; Dietemann, Jean-Louis

    2014-01-01

    To prospectively evaluate the performance of virtual non-calcium (VNC) dual-energy CT (DECT) images for the demonstration of trauma-related abnormal marrow attenuation in collapsed and non-collapsed vertebral compression fractures (VCF) with MRI as a reference standard. Twenty patients presenting with non-tumoral VCF were consecutively and prospectively included in this IRB-approved study, and underwent MRI and DECT of the spine. MR examination served as a reference standard. Two independent readers visually evaluated all vertebrae for abnormal marrow attenuation (''CT edema'') on VNC DECT images; specificity, sensitivity, predictive values, intra and inter-observer agreements were calculated. A last reader performed a quantitative evaluation of CT numbers; cut-off values were calculated using ROC analysis. In the visual analysis, VNC DECT images had an overall sensitivity of 84 %, specificity of 97 %, and accuracy of 95 %, intra- and inter-observer agreements ranged from k = 0.74 to k = 0.90. CT numbers were significantly different between vertebrae with edema on MR and those without (p < 0.0001). Cut-off values provided sensitivity of 85 % (77 %) and specificity of 82 % (74 %) for ''CT edema'' on thoracic (lumbar) vertebrae. VNC DECT images allowed an accurate demonstration of trauma-related abnormal attenuation in VCF, revealing the acute nature of the fracture, on both visual and quantitative evaluation. (orig.)

  11. Dual-energy CT in vertebral compression fractures: performance of visual and quantitative analysis for bone marrow edema demonstration with comparison to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Bierry, Guillaume; Venkatasamy, Aina; Kremer, Stephane; Dosch, Jean-Claude; Dietemann, Jean-Louis [University Hospital of Strasbourg, Department of Radiology, Strasbourg (France)

    2014-04-15

    To prospectively evaluate the performance of virtual non-calcium (VNC) dual-energy CT (DECT) images for the demonstration of trauma-related abnormal marrow attenuation in collapsed and non-collapsed vertebral compression fractures (VCF) with MRI as a reference standard. Twenty patients presenting with non-tumoral VCF were consecutively and prospectively included in this IRB-approved study, and underwent MRI and DECT of the spine. MR examination served as a reference standard. Two independent readers visually evaluated all vertebrae for abnormal marrow attenuation (''CT edema'') on VNC DECT images; specificity, sensitivity, predictive values, intra and inter-observer agreements were calculated. A last reader performed a quantitative evaluation of CT numbers; cut-off values were calculated using ROC analysis. In the visual analysis, VNC DECT images had an overall sensitivity of 84 %, specificity of 97 %, and accuracy of 95 %, intra- and inter-observer agreements ranged from k = 0.74 to k = 0.90. CT numbers were significantly different between vertebrae with edema on MR and those without (p < 0.0001). Cut-off values provided sensitivity of 85 % (77 %) and specificity of 82 % (74 %) for ''CT edema'' on thoracic (lumbar) vertebrae. VNC DECT images allowed an accurate demonstration of trauma-related abnormal attenuation in VCF, revealing the acute nature of the fracture, on both visual and quantitative evaluation. (orig.)

  12. Dual-energy CT in vertebral compression fractures: performance of visual and quantitative analysis for bone marrow edema demonstration with comparison to MRI.

    Science.gov (United States)

    Bierry, Guillaume; Venkatasamy, Aïna; Kremer, Stéphane; Dosch, Jean-Claude; Dietemann, Jean-Louis

    2014-04-01

    To prospectively evaluate the performance of virtual non-calcium (VNC) dual-energy CT (DECT) images for the demonstration of trauma-related abnormal marrow attenuation in collapsed and non-collapsed vertebral compression fractures (VCF) with MRI as a reference standard. Twenty patients presenting with non-tumoral VCF were consecutively and prospectively included in this IRB-approved study, and underwent MRI and DECT of the spine. MR examination served as a reference standard. Two independent readers visually evaluated all vertebrae for abnormal marrow attenuation ("CT edema") on VNC DECT images; specificity, sensitivity, predictive values, intra and inter-observer agreements were calculated. A last reader performed a quantitative evaluation of CT numbers; cut-off values were calculated using ROC analysis. In the visual analysis, VNC DECT images had an overall sensitivity of 84%, specificity of 97%, and accuracy of 95%, intra- and inter-observer agreements ranged from k = 0.74 to k = 0.90. CT numbers were significantly different between vertebrae with edema on MR and those without (p VNC DECT images allowed an accurate demonstration of trauma-related abnormal attenuation in VCF, revealing the acute nature of the fracture, on both visual and quantitative evaluation.

  13. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    Energy Technology Data Exchange (ETDEWEB)

    Pratapas, John; Mather, Daniel; Kozlovsky, Anton

    2013-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen’s significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an

  14. Design and Fabrication of a Dual-Photoelectrode Fuel Cell towards Cost-Effective Electricity Production from Biomass.

    Science.gov (United States)

    Zhang, Bingqing; Fan, Wenjun; Yao, Tingting; Liao, Shichao; Li, Ailong; Li, Deng; Liu, Mingyao; Shi, Jingying; Liao, Shijun; Li, Can

    2017-01-10

    A photo fuel cell (PFC) offers an attractive way to simultaneously convert solar and biomass energy into electricity. Photocatalytic biomass oxidation on a semiconductor photoanode combined with dark electrochemical reduction of oxygen molecules on a metal cathode (usually Pt) in separated compartments is the common configuration for a PFC. Herein, we report a membrane-free PFC based on a dual electrode, including a W-doped BiVO 4 photoanode and polyterthiophene photocathode for solar-stimulated biomass-to-electricity conversion. Air- and water-soluble biomass derivatives can be directly used as reagents. The optimal device yields an open-circuit voltage (V OC ) of 0.62 V, a short-circuit current density (J SC ) of 775 μA cm -2 , and a maximum power density (P max ) of 82 μW cm -2 with glucose as the feedstock under tandem illumination, which outperforms dual-photoelectrode PFCs previously reported. Neither costly separating membranes nor Pt-based catalysts are required in the proposed PFC architecture. Our work may inspire rational device designs for cost-effective electricity generation from renewable resources. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. A comprehensive study on the emission characteristics of E-diesel dual-fuel engine

    Directory of Open Access Journals (Sweden)

    A. Avinash

    2016-03-01

    Full Text Available Each year, the ultimate goal of emission legislation is to force technology to the point where a practically viable zero emission vehicle becomes a reality. Albeit the direction to reach this target is a formidable challenge, homogeneous charge compression ignition (HCCI is a new combustion concept to produce ultra low nitrogen oxides (NOx and smoke emissions. By the way, an endeavor has been made in this work to achieve a simultaneous reduction in both NOx and smoke levels in a direct injection compression ignition engine converted to operate on premixed charge compression ignition mode. Indeed, these promises were made possible in this work by preparing premixed fuel–air mixture outside the engine cylinder. For this purpose, ethanol was injected in the intake port at various premixed ratios (5%, 10%, 15%, 20%, 25% and 30% and conventional diesel was injected as usual. It was extrapolated from the experimental results that e-diesel operation can significantly reduce NOx and smoke levels. In addition, NOx and smoke levels reduced in this experimental study with increase in premixed fraction. Nevertheless, unburned hydrocarbons (UBHC and carbon monoxide (CO emissions exhibited reverse trend with increase in premixed fraction and the maximum value of HC and CO emission levels was noted with 30% premixed fraction.

  16. Influence of injection timing on the exhaust emissions of a dual-fuel CI engine

    Energy Technology Data Exchange (ETDEWEB)

    Sayin, Cenk [Department of Mechanical Education, Marmara University, 34722 Istanbul (Turkey); Uslu, Kadir [Department of Automotive Education, Fatih Vocational High School, 54100 Sakarya (Turkey); Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Kocaeli (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Kocaeli (Turkey)

    2008-06-15

    Environmental concerns and limited amount of petroleum fuels have caused interests in the development of alternative fuels for internal combustion (IC) engines. As an alternative, biodegradable, and renewable fuel, ethanol is receiving increasing attention. Therefore, in this study, influence of injection timing on the exhaust emission of a single cylinder, four stroke, direct injection, naturally aspirated diesel engine has been experimentally investigated using ethanol blended diesel fuel from 0% to 15% with an increment of 5%. The engine has an original injection timing 27 CA BTDC. The tests were performed at five different injection timings (21 , 24 , 27 , 30 , and 33 CA BTDC) by changing the thickness of advance shim. The experimental test results showed that NO{sub x} and CO{sub 2} emissions increased as CO and HC emissions decreased with increasing amount of ethanol in the fuel mixture. When compared to the results of original injection timing, at the retarded injection timings (21 and 24 CA BTDC), NO{sub x} and CO{sub 2} emissions increased, and unburned HC and CO emissions decreased for all test conditions. On the other hand, with the advanced injection timings (30 and 33 CA BTDC), HC and CO emissions diminished, and NO{sub x} and CO{sub 2} emissions boosted for all test conditions. (author)

  17. Measurements of moisture content in wood fuels with dual energy x-ray; Maetning av fukt i biobraenslen med dubbelenergiroentgen

    Energy Technology Data Exchange (ETDEWEB)

    Nordell, Anders [Industriellt Utvecklingscentrum i Karlskoga, Karlskoga (Sweden); Vikterloef, K J [Oerebro Radiofysik AB, Oerebro (Sweden)

    2000-04-01

    Good methods enabling quick determination of moisture in wood fuels are lacking. A standardized method generally used by the biofuel industry means drying samples in furnaces during at least 16 hours. The idea of this work has been to investigate if x-ray technique can offer a superior alternative for fast moisture determination. Analysis with x-ray has many advantages. The x-rays go completely through the whole test specimen. Large samples or many sequential samples can rapidly be measured. The penetration is extraordinary good; all parts of the tested mass will be analyzed. The measurement relies on the absorption of gamma photons in the tested mass. The x-ray absorption is carried out deep down in the atoms and therefore is independent of the materials equation of state as temperature, grain size or molecule binding. The disadvantages of the method are the general anxiety which can be for gamma rays, the relative high cost for equipment and the fact that an x-ray tube will wear with time and needs replacement. The method used here for moisture measurement is known as dual energy x-ray. The test sample is simultaneously exposed to transmission of two separate x-ray energies. The two energies are absorbed differently by the sample. The ratio of the absorption in the two respective energies is calculated and from that conclusions on the composition of the material can be drawn. The equipment used in this test is a standard medical apparatus adapted for the study of human body composition. When instead used for measurements of moisture in wood material the discrimination signal is about half of that achieved in the normal medical case. Despite that, the signal has been good enough for giving satisfactory accuracy in the moisture estimation. A little more than sixty approved results are presented in the report comprehending ten different fuel types. The results are grouped into three main categories depending on fuel type, wood fuels, peat fuels and salix including

  18. Phase 1 remediation of jet fuel contaminated soil and groundwater at JFK International Airport using dual phase extraction and bioventing

    International Nuclear Information System (INIS)

    Roth, R.; Bianco, P. Rizzo, M.

    1995-01-01

    Soil and groundwater contaminated with jet fuel at Terminal One of the JFK International Airport in New York have been remediated using dual phase extraction (DPE) and bioventing. Two areas were remediated using 51 DPE wells and 20 air sparging/air injection wells. The total area remediated by the DPE wells is estimated to be 4.8 acres. Groundwater was extracted to recover nonaqueous phase and aqueous phase jet fuel from the shallow aquifer and treated above ground by the following processes; oil/water separation, iron-oxidation, flocculation, sedimentation, filtration, air stripping and liquid-phase granular activated carbon (LPGAC) adsorption. The extracted vapors were treated by vapor-phase granular activated carbon (VPGAC) adsorption in one area, and catalytic oxidation and VPGAC adsorption in another area. After 6 months of remediation, approximately 5,490 lbs. of volatile organic compounds (VOCs) were removed by soil vapor extraction (SVE), 109,650 lbs. of petroleum hydrocarbons were removed from the extracted groundwater, and 60,550 lbs. of petroleum hydrocarbons were biologically oxidized by subsurface microorganisms. Of these three mechanisms, the rate of petroleum hydrocarbon removal was the highest for biological oxidation in one area and by groundwater extraction in another area

  19. Experimental evaluation of a diesel-biogas dual fuel engine operated on micro-trigeneration system for power, drying and cooling

    International Nuclear Information System (INIS)

    Cacua, Karen; Olmos-Villalba, Luis; Herrera, Bernardo; Gallego, Anderson

    2016-01-01

    Highlights: • A micro-trigeneration system based in a diesel-biogas dual fuel engine was obtained. • Heat from engine exhaust gases was used for drying and refrigeration applications. • Energy efficiency of the microtrigeneration system in dual mode was 40%. • Peppermint was dried in the microtrigeneration system. - Abstract: A micro-trigeneration system based on a diesel-biogas dual fuel engine was evaluated experimentally. In this system, waste heat from the engine exhaust was used for heating air using a heat pipe exchanger and for driving an absorption unit freezer. The air heated was used in a convective trays dryer designed to dry peppermint. The global energy efficiency of this system at the engine full load was 40% and 31% in diesel and dual mode, respectively, while the same efficiencies of the engine at the original single generation were 23% and 18%, respectively. On the other hand, a maximum diesel substitution level of 50% was achieved in dual mode.

  20. An experimental investigation of performance-emission trade off characteristics of a CI engine using hydrogen as dual fuel

    International Nuclear Information System (INIS)

    Deb, Madhujit; Paul, Abhishek; Debroy, Durbadal; Sastry, G.R.K.; Panua, Raj Sekhar; Bose, P.K.

    2015-01-01

    The investigation carried out in this research work concerns the effect of the addition of H 2 on performance and emission characteristics of a single cylinder, 4-stroke diesel engine. The tests were performed using diesel as a pilot fuel, with hydrogen addition at varying load condition using a Timed Manifold Injection (TMI) system has been developed using ECU (electronic control unit) with varying injection strategy to deliver hydrogen on to the intake manifold. The results showed a significant increase in BTE with appreciable decrease in BSEC of the engine when compared to conventional diesel-fueled operation. The emission of CO 2 and NOx was found to increase with enhancement of H 2 addition. The emission of UHC was found to be very high at low load conditions, but it enhanced as the load increased for all hydrogen injection while Soot emissions decreased. Thus, this paper provided a potential to investigate the effect of the addition of H 2 on the performance and emission characteristics of a diesel engine and how to get a best ratio of H 2 addition. The tradeoff study also consolidated the verity that Diesel–H 2 dual fuel operation was instrumental in resolving the high performance – low emission paradox. - Highlights: • Pure diesel and diesel–H 2 blends are tested. • Diesel–H 2 blends produced higher brake thermal efficiency than pure diesel in all part loads. • Diesel–H 2 blends reduced the energy consumption of the engine. • Diesel–H 2 blends simultaneously reduced Soot to some extent but increases N Ox and hydrocarbon emissions. • The performance-emission trade-off paradox has been studied using pure diesel and diesel–H 2 blends

  1. Development of mats composed by TiO{sub 2} and carbon dual electrospun nanofibers: A possible anode material in microbial fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Gomez, Nora A.; Balderas-Renteria, Isaias [Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); Garcia-Gutierrez, Domingo I. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); Universidad Autónoma de Nuevo León, Centro de Innovación, Investigación y Desarrollo en Ingeniería y Tecnología, PIIT, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); Mosqueda, Hugo A. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); and others

    2015-03-15

    Highlights: • Dual nanofiber of TiO{sub 2}–C/C showed excellent electrical performance. • TiO{sub 2}–C/C dual nanofiber can host a dense biofilm of electroactivated Escherichia coli. • Dual nanofibers can be applied as anode to obtain electricity in microbial fuel cells. - Abstract: A new material based on TiO{sub 2(rutile)}–C{sub (semi-graphitic)}/C{sub (semi-graphitic)} dual nanofiber mats is presented, whose composition and synthesis methodology are fundamental factors for the development of exoelectrogenic biofilms on its surface. Therefore, this material shows the required characteristics for possible applications in the bioconversion process of an organic substrate to electricity in a microbial fuel cell. Chronoamperometry, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and electrical conductivity analyses showed excellent electrical performance of the material for the application intended; a resistance as low as 3.149 Ω was able to be measured on this material. Furthermore, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies confirmed the morphology sought on the material for the application intended, dual nanofibres TiO{sub 2(rutile)}–C{sub (semi-graphitic)}/C{sub (semi-graphitic)} with a side by side configuration. The difference in composition of the fibers forming the dual nanofibers was clearly observed and confirmed by energy dispersive X-ray spectroscopy (EDXS), and their crystal structure was evident in the results obtained from selected area electron diffraction (SAED) studies. This nanostructured material presented a high surface area and is biocompatible, given that it can host a dense biofilm of electroactivated Escherichia coli. In this study, the maximum current density obtained in a half microbial fuel cell was 8 A/m{sup 2} (0.8 mA/cm{sup 2})

  2. Desempeño y emisiones de un motor de combustión interna con combustible dual Diesel – Gas natural ;Performance and emissions study of an internal combustion engine with dual fuel diesel - natural gas

    Directory of Open Access Journals (Sweden)

    Juan Miguel Mantilla González

    2015-04-01

    Full Text Available Muchos de los problemas reportados para los sistemas duales diesel- gas natural ocurren por mala dosificación del gas. Por esta razón se adaptó un sistema de alimentación dual con inyección electrónica de gas natural a un motor de combustión interna encendido por compresión. Se plantea un diseño experimental controlando el dosado de gas natural.Como resultado se obtiene un análisis comparativo entre los valoresde desempeño y emisiones desde la operación Diesel y Diesel-Gas natural. A partir de este análisis es posible observar que el desempeño del motor no se ve afectado por la operación del motor bajo el esquema Dual Diesel-GN, es decir que el motor funcionando bajo modo dual puede sostener las cargas solicitadas al motor. También se observa que la eficiencia volumétrica mejora bajo todas las condiciones de operación dual y las emisiones son mejores sólo cuando el motor trabaja a altas cargas. Many of the problems reported for dual diesel-natural gas systems occur due to poor gas dosage. For this reason a natural gas electronic injection feeding system was adapted to a compression ignitios internal combustion engine. An experimental design controlling the natural gas dosage is considered. As a result a comparative analysis between performance and emissions from the Diesel-and diesel-Natural Gas operation is obtained. From this analysis it is possible to see that engine performance is not affected by operation of the engine under the dual mode, i.e. the motor running under dual mode can support the loads applied to the engine. It is also observed that the volumetric efficiency improves under all conditions of operation and emissions from the dual mode of operation are better only when working at high engine loads.

  3. Autoignition characterization of primary reference fuels and n-heptane/n-butanol mixtures in a constant volume combustion device and homogeneous charge compression ignition engine

    KAUST Repository

    Baumgardner, Marc E.

    2013-12-19

    In this study, the autoignition behavior of primary reference fuels (PRF) and blends of n-heptane/n-butanol were examined in a Waukesha Fuel Ignition Tester (FIT) and a Homogeneous Charge Compression Engine (HCCI). Fourteen different blends of iso-octane, n-heptane, and n-butanol were tested in the FIT - 28 test runs with 25 ignition measurements for each test run, totaling 350 individual tests in all. These experimental results supported previous findings that fuel blends with high alcohol content can exhibit very different ignition delay periods than similarly blended reference fuels. The experiments further showed that n-butanol blends behaved unlike PRF blends when comparing the autoignition behavior as a function of the percentage of low reactivity component. The HCCI and FIT experimental results favorably compared against single and multizone models with detailed chemical kinetic mechanisms - both an existing mechanism as well as one developed during this study were used. The experimental and modeling results suggest that that the FIT instrument is a valuable tool for analysis of high pressure, low temperature chemistry, and autoignition for future fuels in advanced combustion engines. Additionally, in both the FIT and engine experiments the fraction of low temperature heat release (fLTHR) was found to correlate very well with the crank angle of maximum heat release and shows promise as a useful metric for fuel reactivity in advanced combustion applications. © 2013 American Chemical Society.

  4. Aircraft dual-shaft jet engine with indirect action fuel flow controller

    Science.gov (United States)

    Tudosie, Alexandru-Nicolae

    2017-06-01

    The paper deals with an aircraft single-jet engine's control system, based on a fuel flow controller. Considering the engine as controlled object and its thrust the most important operation effect, from the multitude of engine's parameters only its rotational speed n is measurable and proportional to its thrust, so engine's speed has become the most important controlled parameter. Engine's control system is based on fuel injection Qi dosage, while the output is engine's speed n. Based on embedded system's main parts' mathematical models, the author has described the system by its block diagram with transfer functions; furthermore, some Simulink-Matlab simulations are performed, concerning embedded system quality (its output parameters time behavior) and, meanwhile, some conclusions concerning engine's parameters mutual influences are revealed. Quantitative determinations are based on author's previous research results and contributions, as well as on existing models (taken from technical literature). The method can be extended for any multi-spool engine, single- or twin-jet.

  5. Pressure loss coefficient and flow rate of side hole in a lower end plug for dual-cooled annular nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Chang-Hwan, E-mail: shinch@kaeri.re.kr; Park, Ju-Yong, E-mail: juyong@kaeri.re.kr; In, Wang-Kee, E-mail: wkin@kaeri.re.kr

    2013-12-15

    Highlights: • A lower end plug with side flow holes is suggested to provide alternative flow paths of the inner channel. • The inlet loss coefficient of the lower end plug is estimated from the experiment. • The flow rate through the side holes is estimated in a complete entrance blockage of inner channel. • The consequence in the reactor core condition is evaluated with a subchannel analysis code. - Abstract: Dual-cooled annular nuclear fuel for a pressurized water reactor (PWR) has been introduced for a significant increase in reactor power. KAERI has been developing a dual-cooled annular fuel for a power uprate of 20% in an optimized PWR in Korea, the OPR1000. This annular fuel can help decrease the fuel temperature substantially relative to conventional cylindrical fuel at a power uprate. Annular fuel has dual flow channels around itself; however, the inner flow channel has a weakness in that it is isolated unlike the outer flow channel, which is open to other neighbouring outer channels for a coolant exchange in the reactor core. If the entrance of the inner channel is, as a hypothetical event, completely blocked by debris, the inner channel will then experience a rapid increase in coolant temperature such that a departure from nucleate boiling (DNB) may occur. Therefore, a remedy to avoid such a postulated accident is indispensable for the safety of annular fuel. A lower end plug with side flow holes was suggested to provide alternative flow paths in addition to the central entrance of the inner channel. In this paper, the inlet loss coefficient of the lower end plug and the flow rate through the side holes were estimated from the experimental results even in a complete entrance blockage of the inner channel. An optimization for the side hole was also performed, and the results are applied to a subchannel analysis to evaluate the consequence in the reactor core condition.

  6. Studi Eksperimen Unjuk Kerja Mesin Diesel Menggunakan Sistem Dual Fuel Solar Gas CNG Dengan Variasi Tekanan Injeksi Gas Dan Derajat Waktu Injeksi

    Directory of Open Access Journals (Sweden)

    Dicky Yoko Exoryanto

    2017-01-01

    Full Text Available Bahan bakar gas ini jika ditinjau dari ekonomis tergolong sangat murah dan ramah lingkungan. Namun, pengaplikasian bahan bakar gas CNG pada generator diesel dengan sistem dual fuel berdampak pada penurunan performansinya. Hal ini terjadi karena rasio campuran udara dan bahan bakar pada sistem dual fuel belum sesuai, sehingga perlunya penelitian lebih lanjut. Penelitian ini bertujuan untuk meningkatkan performa pada mesin diesel dengan memodifikasi saluran masuk udara dengan memasang injector gas CNG untuk memasukkan bahan bakar tersebut kedalam ruang bakar sehingga mesin diesel berubah menjadi sitem dual fuel. Tidak hanya saluran masuk udara saja yang di modifikasi tetapi, variasi start of injection dan tekanan gas yang masuk juga di variasikan. Penelitian ini di lakukan secara eksperimental dengan menginjeksikan gas CNG ke dalam ruang bakar melalui saluran hisap yang sudah terpasang injector. Proses pengaturan injeksi gas CNG diatur oleh ECU programamble melalui software VEMSTUNE. Sistem pengaturan yang dilakukan adalah mengatur derajat waktu injection (SOI dengan nilai 5o, 30o, 55o, dan 80o CA BTDC dan variasi tekanan masuk gas CNG dengan nilai 1, 1,5, 2, dan 2,5 N/m2. Penelitian ini dilakukan dengan putaran mesin konstan sebesar 2000 rpm dengan beban 0 sampai 100 %. Hasil yang didapatkan dari eksperimen yang dilakukan kali ini, antara lain : performa dual fuel lebih optimal dibandingkan saat pengoperasian single fuel. Pengaturan paling optimal terjadi pada start of injection 80° CA BTDC dengan tekanan 1,5 gas CNG. Gas CNG dapat menggantikan porsi bahan bakar minyak solar sebesar 45,30 %. Nilai subtitusi minyak solar yang optimal sebesar 61,39 % dan SFC minyak solar rata-rata mengalami penurunan sebesar 47,10 %, tetapi SFC dual fuel rata-rata meningkat sebesar 47,67 % dibandingkan SFC single fuel. Nilai rata-rata efisiensi thermal turun sebesar 40,89 %, nilai AFR rata-rata turun dari 25,60 menjadi 12,90 dan Temperatur gas buang meningkat dari

  7. The Miller cycle effects on improvement of fuel economy in a highly boosted, high compression ratio, direct-injection gasoline engine: EIVC vs. LIVC

    International Nuclear Information System (INIS)

    Li, Tie; Gao, Yi; Wang, Jiasheng; Chen, Ziqian

    2014-01-01

    Highlights: • At high load, LIVC is superior over EIVC in improving fuel economy. • The improvement with LIVC is due to advanced combustion phasing and increased pumping work. • At low load, EIVC is better than LIVC in improving fuel economy. • Pumping loss with EIVC is smaller than with LIVC at low load. • But heat release rate with EIVC is slower than with LIVC. - Abstract: A combination of downsizing, highly boosting and direct injection (DI) is an effective way to improve fuel economy of gasoline engines without the penalties of reduced torque or power output. At high loads, however, knock problem becomes severer when increasing the intake boosting. As a compromise, geometric compression ratio (CR) is usually reduced to mitigate knock, and the improvement of fuel economy is discounted. Application of Miller cycle, which can be realized by either early or late intake valve closing (EIVC or LIVC), has the potential to reduce the effective CR and suppress knock. In this paper, the effects of EIVC and LIVC on the fuel economy of a boosted DI gasoline production engine reformed with a geometric CR of 12.0 are experimentally compared at low and high loads. Compared to the original production engine with CR 9.3, at the high load operation, the brake specific fuel consumption (BSFC) is improved by 4.7% with CR12.0 and LIVC, while the effect of EIVC on improving BSFC is negligibly small. At the low load operation, combined with CR12.0, LIVC and EIVC improve the fuel economy by 6.8% and 7.4%, respectively, compared to the production engine. The mechanism behind the effects of LIVC and EIVC on improving the fuel economy is discussed. These results will be a valuable reference for engine designers and researchers

  8. Influence of fuel type, dilution and equivalence ratio on the emission reduction from the auto-ignition in an Homogeneous Charge Compression Ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Machrafi, Hatim [UPMC Universite Paris 06, ENSCP, 11 rue de Pierre et Marie Curie, 75005 Paris (France); UPMC Universite Paris 06, Institut Jean Le Rond D' Alembert, 4 place Jussieu, 75252 Paris cedex 05 (France); Universite Libre de Bruxelles, TIPs - Fluid Physics, CP165/67, 50 Avenue F.D. Roosevelt, 1050 Brussels (Belgium); Cavadias, Simeon [UPMC Universite Paris 06, ENSCP, 11 rue de Pierre et Marie Curie, 75005 Paris (France); UPMC Universite Paris 06, Institut Jean Le Rond D' Alembert, 4 place Jussieu, 75252 Paris cedex 05 (France); Amouroux, Jacques [UPMC Universite Paris 06, ENSCP, 11 rue de Pierre et Marie Curie, 75005 Paris (France)

    2010-04-15

    One technology that seems to be promising for automobile pollution reduction is the Homogeneous Charge Compression Ignition (HCCI). This technology still faces auto-ignition and emission-control problems. This paper focuses on the emission problem, since it is incumbent to realize engines that pollute less. For this purpose, this paper presents results concerning the measurement of the emissions of CO, NO{sub x}, CO{sub 2}, O{sub 2} and hydrocarbons. HCCI conditions are used, with equivalence ratios between 0.26 and 0.54, inlet temperatures of 70 C and 120 C and compression ratios of 10.2 and 13.5, with different fuel types: gasoline, gasoline surrogate, diesel, diesel surrogate and mixtures of n-heptane/toluene. The effect of dilution is considered for gasoline, while the effect of the equivalence ratio is considered for all the fuels. No significant amount of NO{sub x} has been measured. It appeared that the CO, O{sub 2} and hydrocarbon emissions were reduced by decreasing the toluene content of the fuel and by decreasing the dilution. The opposite holds for CO{sub 2}. The reduction of the hydrocarbon emission appears to compete with the reduction of the CO{sub 2} emission. Diesel seemed to produce less CO and hydrocarbons than gasoline when auto-ignited. An example of emission reduction control is presented in this paper. (author)

  9. Effect of fuel oxygen on the energetic and exergetic efficiency of a compression ignition engine fuelled separately with palm and karanja biodiesels

    International Nuclear Information System (INIS)

    Jena, Jibanananda; Misra, Rahul Dev

    2014-01-01

    Exergy analysis of any thermodynamic system can take care of the limitations of energy analysis such as irreversible losses, their magnitude and the source of thermodynamic inefficiencies apart from energy losses. In the present study, both the analyses along with heat release analysis are conducted on a natural aspirated diesel engine fuelled separately with palm biodiesel (PB), karanja biodiesel (KB), and petrodiesel (PD) using the experimental data. Since the engine performs best at about 85% loading condition, the energetic and exergetic performance parameters of the engine are evaluated at 85% loading condition for each type of fuel. The aim of the study is to determine the effect of fuel oxygen on energy and exergy efficiencies of a CI (compression ignition) engine. Various exergy losses, exergy destruction and their ratios associated with the heat transfer through cooling water, radiation, exhaust gas, friction, and some uncounted exergy destruction are investigated. Apart from exergy loss due to heat transfer; the uncounted exergy destruction (due to combustion) also plays a major role in the system inefficiency. Based on the comparative assessment of the obtained results, it is concluded that a better combustion with less irreversibility is possible with the increase in O 2 content in the fuel. - Highlights: • Efficiency of a CI engine increases with the increase in oxygen quantity in the fuel. • Irreversibility of a CI engine decreases with increase in oxygen content in the fuel. • Palm biodiesel performs better than karanja biodiesel and petrodiesel for a CI engine

  10. Clean air program : design guidelines for bus transit systems using compressed natural gas as an alternative fuel

    Science.gov (United States)

    1996-06-01

    This report documents design guidelines for the safe use of Compressed Natural Gas (CNG). The report is designed to provide guidance, information on safe industry practices, applicable national codes and standards, and reference data that transit age...

  11. Effect of a dual-purpose cask payload increment of spent fuel assemblies from VVER 1000 Bushehr Nuclear Power Plant on basket criticality

    International Nuclear Information System (INIS)

    Rezaeian, M.; Kamali, J.

    2017-01-01

    Dual-purpose casks can be utilized for dry interim storage and transportation of the highly radioactive spent fuel assemblies (SFAs) of Bushehr Nuclear Power Plant (NPP). Criticality safety analysis was carried out using the MCNP code for the cask containing 12, 18, or 19 SFAs. The basket materials of borated stainless steel and Boral (Al-B_4C) were investigated, and the minimum required receptacle pitch of the basket was determined. - Highlights: • Criticality safety analysis for a dual purpose cask was carried out. • The basket material of borated stainless steel and Boral were investigated. • Minimum receptacle pitch was determined for 12, 18, or 19 VVER 1000 spent fuel assemblies.

  12. Effects of combustion efficiency on a Dual cycle

    International Nuclear Information System (INIS)

    Ozsoysal, Osman Azmi

    2009-01-01

    This paper studies a Dual cycle model containing irreversibilities coming exclusively from expansion and compression processes. It is assumed that any fraction of the fuel's chemical energy can not fully released inside the engine because of the incomplete combustion. Utilizing the combustion efficiency is found to be more useful to realize the cycle feasibility. Amount of the released energy from fuel into the cylinder restricts the compression ratio. It is presented how the upper limit of compression ratio is evaluated by means of using some constraints for realizing a Dual cycle. Valid ranges of the constraints given in literature seriously affect the feasibility of cycle. Developed mathematical model leads to a qualitative understanding of how engine loss can be reduced. Thermal efficiency-work curves cannot have a closed loop shape because there is a close relationship between the fuel energy, air-fuel mass ratio, combustion efficiency, maximum cycle temperature and the heat losses into the cylinder wall. If these are all omitted, while heat losses are determined independently without establishing any relationship between the released fuel energy, the thermal efficiency versus work curves will just be able to have a closed loop shape. This is the original perspective and contribution of paper.

  13. Optimization of a dual-fuel heating system utilizing an EMS a maintain persistence of measures

    International Nuclear Information System (INIS)

    Wolpert, J.S.; Wolpert, S.B.; Martin, G.

    1993-01-01

    An older small office building was subjected to a program substituting gas for electric heat to reduce energy cost and improve comfort for approximately one year and was permanently instituted, with the installation of an energy management system (EMS) the following year. This paper will present a description of the facility, its usage patterns, and the measures taken to introduce the fuel-switching program. The impacts on energy usage and cost as well as comfort will also be reported. This program was initiated by a preliminary audit of the facility conducted by the service contractor in conjunction with the area gas wholesaler. During the audit it was observed that the heating set points for the gas-fired equipment was kept fairly low. This was the result of the desire to keep the cooling set point low and the use of auto-changeover thermostats. The result of this was that the system utilized the gas heat to come up to 68-70 degrees with the majority of the zones then relying on their electric heat to bring temperatures into the 73-75 degrees range. In addition to impacting energy costs, this approach generated numerous comfort complaints. As a further electric penalty, the low cooling set point resulted in a heavy reliance on electric heat (reheat) all summer. The basis of the proposed strategy was to reduce the heavy usage of electric heat by making the building comfortable through reliance more heavily on gas heat. This was tested by raising the heating set points for the RTUS. The success of this approach, along with the comfort considerations and the desire for further savings, led to the installation of an EMS. This allowed further refinements of the control strategy, which are briefly described. When completed, the fuel-switching led to an increase in annual gas costs of 125% with a corresponding decrease in electric cost of nearly 30% for an annual utility cost savings of over 19%

  14. Characterization of performance-emission indices of a diesel engine using ANFIS operating in dual-fuel mode with LPG

    Science.gov (United States)

    Chakraborty, Amitav; Roy, Sumit; Banerjee, Rahul

    2018-03-01

    This experimental work highlights the inherent capability of an adaptive-neuro fuzzy inference system (ANFIS) based model to act as a robust system identification tool (SIT) in prognosticating the performance and emission parameters of an existing diesel engine running of diesel-LPG dual fuel mode. The developed model proved its adeptness by successfully harnessing the effects of the input parameters of load, injection duration and LPG energy share on output parameters of BSFCEQ, BTE, NOX, SOOT, CO and HC. Successive evaluation of the ANFIS model, revealed high levels of resemblance with the already forecasted ANN results for the same input parameters and it was evident that similar to ANN, ANFIS also has the innate ability to act as a robust SIT. The ANFIS predicted data harmonized the experimental data with high overall accuracy. The correlation coefficient (R) values are stretched in between 0.99207 to 0.999988. The mean absolute percentage error (MAPE) tallies were recorded in the range of 0.02-0.173% with the root mean square errors (RMSE) in acceptable margins. Hence the developed model is capable of emulating the actual engine parameters with commendable ranges of accuracy, which in turn would act as a robust prediction platform in the future domains of optimization.

  15. Optimization of culture conditions and electricity generation using Geobacter sulfurreducens in a dual-chambered microbial fuel-cell

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi-Sun; Lee, Yu-jin [Bioenergy Research Center, Korea Institute of Energy Research, Daejeon 305-343 (Korea, Republic of)

    2010-12-15

    The promise of generating electricity from the oxidation of organic substances using metal-reducing bacteria is drawing attention as an alternate form of bio-technology with positive environmental implications. In this study, we examined various experimental factors to obtain the maximum power output in a dual-chamber mediator-less microbial fuel-cell (MFC) using Geobacter sulfurreducens and acetate as an electron donor in a semi-continuous mode. The G. sulfurreducens culture conditions were optimized in a nutrient buffer containing 20 mM of acetate and 50 mM of fumarate at pH 6.8 and 30 C. For use in the MFC system, electrodes were made with carbon paper (area: 11.5 cm{sup 2}) and spaced 1.5 cm apart. Once the MFC was inoculated with the pre-cultured G. sulfurreducens in the anode chamber and while air was continuously sparged to the cathode chamber, the cells produced electricity stably over 60 days with the regular addition of 20 mM acetate, generating the maximum power density of 7 mW/m{sup 2} with a 5000 and ohm; load. The current output was significantly increased, by 1.6 times after 20 days of incubation under the same experimental conditions, when the carbon-paper anode was coated with carbon nanotubes. (author)

  16. Effect of compression ratio, equivalence ratio and engine speed on the performance and emission characteristics of a spark ignition engine using hydrogen as a fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sadiq Al-Baghdadi, M.A.R. [University of Babylon (Iraq). Dept. of Mechanical Engineering

    2004-12-01

    The present energy situation has stimulated active research interest in non-petroleum and non-polluting fuels, particularly for transportation, power generation, and agricultural sectors. Researchers have found that hydrogen presents the best and an unprecedented solution to the energy crises and pollution problems, due to its superior combustion qualities and availability. This paper discusses analytically and provides data on the effect of compression ratio, equivalence ratio and engine speed on the engine performance, emissions and pre-ignition limits of a spark ignition engine operating on hydrogen fuel. These data are important in order to understand the interaction between engine performance and emission parameters, which will help engine designers when designing for hydrogen. (author)

  17. Biodiesel production from Cynara cardunculus L. and Brassica carinata A. Braun seeds and their suitability as fuels in compression ignition engines

    Directory of Open Access Journals (Sweden)

    Stefania De Domenico

    2016-03-01

    Full Text Available The development of energy crops can provide environmental benefits and may represent an opportunity to improve agriculture in areas considered at low productivity. In this work, we studied the energy potential of two species (Brassica carinata A. Braun and Cynara cardunculus L. and their seed oil productivity under different growth conditions. Furthermore, the biodiesel from the oil extracted from the seeds of these species was produced and analysed in term of utilisation as fuels in compression ignition engines. In particular, the spray penetration and shape ratio were measured in a constant-volume chamber and compared with the results obtained with a standard diesel fuel. These results were obtained using a standard common rail injection system at different injection pressure, injection duration, and constant-volume chamber pressure.

  18. Effects of Direct Fuel Injection Strategies on Cycle-by-Cycle Variability in a Gasoline Homogeneous Charge Compression Ignition Engine: Sample Entropy Analysis

    Directory of Open Access Journals (Sweden)

    Jacek Hunicz

    2015-01-01

    Full Text Available In this study we summarize and analyze experimental observations of cyclic variability in homogeneous charge compression ignition (HCCI combustion in a single-cylinder gasoline engine. The engine was configured with negative valve overlap (NVO to trap residual gases from prior cycles and thus enable auto-ignition in successive cycles. Correlations were developed between different fuel injection strategies and cycle average combustion and work output profiles. Hypothesized physical mechanisms based on these correlations were then compared with trends in cycle-by-cycle predictability as revealed by sample entropy. The results of these comparisons help to clarify how fuel injection strategy can interact with prior cycle effects to affect combustion stability and so contribute to design control methods for HCCI engines.

  19. Comparison of thermal, radical and chemical effects of EGR gases using availability analysis in dual-fuel engines at part loads

    International Nuclear Information System (INIS)

    Hosseinzadeh, A.; Khoshbakhti Saray, R.; Seyed Mahmoudi, S.M.

    2010-01-01

    Dual-fuel engines at part load inevitably suffer from lower thermal efficiency and higher emission of carbon monoxide and unburned fuel. A quasi-two-zone combustion model has been developed for studying the second-law analysis of a dual-fuel (diesel-gas) engine operating under part-load conditions. The model is composed of two divisions: a single-zone combustion model with chemical kinetics for combustion of natural gas fuel and a subsidiary zone for combustion of pilot fuel. In the latter zone, the pilot fuel is considered as a heat source derived from two superposed Wiebe's combustion functions to account for contribution of pilot fuel in ignition of gaseous fuel and the rest of the total released energy. This quasi-two-zone combustion model is able to establish the development of combustion process with time and associated important operating parameters, such as pressure, temperature, heat release rate (HRR) and species concentration. The present work is an attempt to investigate the combustion phenomenon from second-law point of view at part load and using exhaust gas recirculation (EGR) to improve the aforementioned problems. Therefore, the availability analysis is applied to the engine from inlet valve closing (IVC) until exhaust valve opening (EVO). Various availability components are identified and calculated separately with crank position. In this paper, the various availability components are identified and calculated separately with crank position. Then the different cases of EGR (chemical, radical and thermal cases) are applied to the availability analysis in dual-fuel engines at part loads. It is found that the chemical case of EGR has negative effect and in this case the unburned chemical availability is increased and the work availability decreases in comparison with baseline engine (without EGR). While the thermal and radical cases have positive effects on the availability terms especially on the unburned chemical availability and work availability

  20. Isotopic Tracing of Particulate Matter from a Compression Ignition Engine Fueled with Ethanol-in-Diesel Blends

    International Nuclear Information System (INIS)

    Cheng, A.S.; Dibble, R.W.; Buchholz, B.

    1999-01-01

    Accelerator Mass Spectrometry (AMS) was used to investigate the relative contribution to diesel engine particulate matter (PM) from the ethanol and diesel fractions of blended fuels. Four test fuels along with a diesel fuel baseline were investigated. The test fuels were comprised of 14 C depleted diesel fuel mixed with contemporary grain ethanol (>400 the 14 C concentration of diesel). An emulsifier (Span 85) or cosolvent (butyl alcohol) was used to facilitate mixing. The experimental test engine was a 1993 Cummins B5.9 diesel rated at 175 hp at 2500 rpm. Test fuels were run at steady-state conditions of 1600 rpm and 210 ft-lbs, and PM samples were collected on quartz filters following dilution of engine exhaust in a mini-dilution tunnel. AMS analysis of the filter samples showed that the ethanol contributed less to PM relative to its fraction in the fuel blend. For the emulsified blends, 6.4% and 10.3% contributions to PM were observed for 11.5% and 23.0% ethanol fuels, respectively. For the cosolvent blends, even lower contributions were observed (3.8% and 6.3% contributions to PM for 12.5% and 25.0% ethanol fuels, respectively)

  1. Pressure-time characteristics in diesel engine fueled with natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Selim, Mohamed Y.E. [Helwan Univ., Mechanical Power Engineering Dept., Cairo (Egypt)

    2001-04-01

    Combustion pressure data are measured and presented for a dual fuel engine running on dual fuel of diesel and compressed natural gas, and compared to the diesel engine case. The maximum pressure rise rate during combustion is presented as a measure of combustion noise. Experimental investigation on diesel and dual fuel engines revealed the noise generated from combustion in both cases. A Ricardo E6 diesel version engine is converted to run on dual fuel of diesel and compressed natural gas and is used throughout the work. The engine is fully computerized and the cylinder pressure data, crank angle data are stored in a PC for off-line analysis. The effect of engine speeds, loads, pilot injection angle, and pilot fuel quantity on combustion noise is examined for both diesel and dual engine. Maximum pressure rise rate and some samples of ensemble averaged pressure-crank angle data are presented in the present work. The combustion noise, generally, is found to increase for the dual fuel engine case as compared to the diesel engine case. (Author)

  2. Economical and environmental assessments of compressed natural gas for diesel vehicle in Thailand

    Directory of Open Access Journals (Sweden)

    Prateep Chouykerd

    2008-08-01

    Full Text Available The economic assessments for the use of compressed natural gas as fuel for several types of diesel vehicles, rarely pick up, non-fixed route truck and private truck, were studied. It is noted that two main technologies of diesel natural gas vehicle (NGV, i.e. dedicated retrofit and diesel dual fuel (DDF, were considered in this work. It was found that the dedicated retrofit needs higher investment costs than dual fuel, but can achieve higher diesel saving than dual fuel. In detail, the payback period of dual fuel non-fixed route truck was found to be identical to dual fuel private truck both in the cases of6 wheel and 10 wheel, while dedicated retrofit non-fixed route truck and private truck are also identical and have longerpay back period than dual fuel due to its higher conversion costs.This work also presents the emissions released from all types of engines especially green house gas CO2. It was found that, in the case of light duty diesel i.e. pickup truck, dedicated retrofit emitted high level of CO2 than both dual fuel and conventional diesel engines. For heavy duty i.e. non-fixed route truck and private truck vehicles, dedicated retrofit emitted a lower level of CO2 than normal diesel engine. Other pollutants from engine emission, i.e. hydrocarbon (HC,nitric oxide (NOx, carbon monoxide (CO and particulate matter, (PM were also observed. The results indicated that, inthe case of light duty diesel, dedicated retrofit engine emits higher levels of HC and CO than diesel engine; in contrast, it emits lower level of NOx and PM than diesel and dual fuel. Dual fuel emits HC and CO higher than diesel and dedicated retrofit but emits lower level of NOx and PM than diesel. Lastly, for heavy duty diesel, it was demonstrated that non-fixed route truck and private truck heavy duty dedicated retrofit have potential to reduce emissions of HC, NOx, CO and PM when compared to normal heavy duty diesel. Engine efficiencies under dual fuel and dedicated

  3. Development of a Fast Breeder Reactor Fuel Bundle Deformation Analysis Code - BAMBOO: Development of a Pin Dispersion Model and Verification by the Out-of-Pile Compression Test

    International Nuclear Information System (INIS)

    Uwaba, Tomoyuki; Ito, Masahiro; Ukai, Shigeharu

    2004-01-01

    To analyze the wire-wrapped fast breeder reactor fuel pin bundle deformation under bundle/duct interaction conditions, the Japan Nuclear Cycle Development Institute has developed the BAMBOO computer code. This code uses the three-dimensional beam element to calculate fuel pin bowing and cladding oval distortion as the primary deformation mechanisms in a fuel pin bundle. The pin dispersion, which is disarrangement of pins in a bundle and would occur during irradiation, was modeled in this code to evaluate its effect on bundle deformation. By applying the contact analysis method commonly used in the finite element method, this model considers the contact conditions at various axial positions as well as the nodal points and can analyze the irregular arrangement of fuel pins with the deviation of the wire configuration.The dispersion model was introduced in the BAMBOO code and verified by using the results of the out-of-pile compression test of the bundle, where the dispersion was caused by the deviation of the wire position. And the effect of the dispersion on the bundle deformation was evaluated based on the analysis results of the code

  4. Engine performance, combustion, and emissions study of biomass to liquid fuel in a compression-ignition engine

    International Nuclear Information System (INIS)

    Ogunkoya, Dolanimi; Fang, Tiegang

    2015-01-01

    Highlights: • Renewable biomass to liquid (BTL) fuel was tested in a direct injection diesel engine. • Engine performance, in-cylinder pressure, and exhaust emissions were measured. • BTL fuel reduces pollutant emission for most conditions compared with diesel and biodiesel. • BTL fuel leads to high thermal efficiency and lower fuel consumption compared with diesel and biodiesel. - Abstract: In this work, the effects of diesel, biodiesel and biomass to liquid (BTL) fuels are investigated in a single-cylinder diesel engine at a fixed speed (2000 rpm) and three engine loads corresponding to 0 bar, 1.26 bar and 3.77 bar brake mean effective pressure (BMEP). The engine performance, in-cylinder combustion, and exhaust emissions were measured. Results show an increase in indicated work for BTL and biodiesel at 1.26 bar and 3.77 bar BMEP when compared to diesel but a decrease at 0 bar. Lower mechanical efficiency was observed for BTL and biodiesel at 1.26 bar BMEP but all three fuels had roughly the same mechanical efficiency at 3.77 bar BMEP. BTL was found to have the lowest brake specific fuel consumption (BSFC) and the highest brake thermal efficiency (BTE) among the three fuels tested. Combustion profiles for the three fuels were observed to vary depending on the engine load. Biodiesel was seen to have the shortest ignition delay among the three fuels regardless of engine loads. Diesel had the longest ignition delay at 0 bar and 3.77 bar BMEP but had the same ignition delay as BTL at 1.26 bar BMEP. At 1.26 bar and 3.77 bar BMEP, BTL had the lowest HC emissions but highest HC emissions at no load conditions when compared to biodiesel and diesel. When compared to diesel and biodiesel BTL had lower CO and CO 2 emissions. At 0 bar and 1.26 bar BMEP, BTL had higher NOx emissions than diesel fuel but lower NOx than biodiesel at no load conditions. At the highest engine load tested, NOx emissions were observed to be highest for diesel fuel but lowest for BTL. At 1

  5. Research on high-temperature compression and creep behavior of porous Cu–Ni–Cr alloy for molten carbonate fuel cell anodes

    Directory of Open Access Journals (Sweden)

    Li W.

    2015-06-01

    Full Text Available The effect of porosity on high temperature compression and creep behavior of porous Cu alloy for the new molten carbonate fuel cell anodes was examined. Optical microscopy and scanning electron microscopy were used to investigate and analyze the details of the microstructure and surface deformation. Compression creep tests were utilized to evaluate the mechanical properties of the alloy at 650 °C. The compression strength, elastic modulus, and yield stress all increased with the decrease in porosity. Under the same creep stress, the materials with higher porosity exhibited inferior creep resistance and higher steadystate creep rate. The creep behavior has been classified in terms of two stages. The first stage relates to grain rearrangement which results from the destruction of large pores by the applied load. In the second stage, small pores are collapsed by a subsequent sintering process under the load. The main deformation mechanism consists in that several deformation bands generate sequentially under the perpendicular loading, and in these deformation bands the pores are deformed by flattering and collapsing sequentially. On the other hand, the shape of a pore has a severe influence on the creep resistance of the material, i.e. every increase of pore size corresponds to a decrease in creep resistance.

  6. Economic assessment and energy model scenarios of municipal solid waste incineration and gas turbine hybrid dual-fueled cycles in Thailand

    International Nuclear Information System (INIS)

    Udomsri, Seksan; Martin, Andrew R.; Fransson, Torsten H.

    2010-01-01

    Finding environmentally benign methods related to sound municipal solid waste (MSW) management is of highest priority in Southeast Asia. It is very important to study new approaches which can reduce waste generation and simultaneously enhance energy recovery. One concrete example of particular significance is the concept of hybrid dual-fuel power plants featuring MSW and another high-quality fuel like natural gas. The hybrid dual-fuel cycles provide significantly higher electrical efficiencies than a composite of separate single-fuel power plant (standalone gas turbine combined cycle and MSW incineration). Although hybrid versions are of great importance for energy conversion from MSW, an economic assessment of these systems must be addressed for a realistic appraisal of these technologies. This paper aims to further examine an economic assessment and energy model analysis of different conversion technologies. Energy models are developed to further refine the expected potential of MSW incineration with regards to energy recovery and environmental issues. Results show that MSW incineration can play role for greenhouse gas reduction, energy recovery and waste management. In Bangkok, the electric power production via conventional incineration and hybrid power plants can cover 2.5% and 8% of total electricity consumption, respectively. The hybrid power plants have a relative short payback period (5 years) and can further reduce the CO 2 levels by 3% in comparison with current thermal power plants.

  7. Research on the combustion, energy and emission parameters of diesel fuel and a biomass-to-liquid (BTL) fuel blend in a compression-ignition engine

    International Nuclear Information System (INIS)

    Rimkus, Alfredas; Žaglinskis, Justas; Rapalis, Paulius; Skačkauskas, Paulius

    2015-01-01

    Highlights: • Researched physical–chemical and performance properties of diesel fuel and BTL blend (85/15 V/V). • BTL additive reduced Brake Specific Fuel Consumption, improved engine efficiency. • Simpler BTL molecular chains and lower C/H ratio reduced CO_2 emission and smokiness. • Higher cetane number of BTL reduced heat release in beginning of combustion and NO_x emission. • Advanced start of fuel injection caused reduced fuel consumption and smokiness, increased NO_x emission. - Abstract: This paper presents the comparable research results of the physical–chemical and direct injection (DI) diesel engine properties of diesel fuel and BTL (biomass-to-liquid) blend (85/15 V/V). The energy, ecological and in-cylinder parameters were analysed under medium engine speed and brake torque load regimes; the start of fuel injection was also adjusted. After analysis of the engine bench tests and simulation with AVL BOOST software, it was observed that the BTL additive shortened the fuel ignition delay phase, reduced the heat release in the pre-mixed intensive combustion phase, reduced the nitrogen oxide (NO_x) concentration in the engine exhaust gases and reduced the thermal and mechanical load of the crankshaft mechanism. BTL additive reduced the rates of carbon dioxide (CO_2), incompletely burned hydrocarbons (HC) emission and smokiness due to its chemical composition and combustion features. BTL also reduced Brake Specific Fuel Consumption (BSFC, g/kW h) and improved engine efficiency (η_e); however, the volumetric fuel consumption changed due to the lower density of BTL. The start of fuel injection was adjusted for maximum engine efficiency; concomitantly, reductions in the CO_2 concentration, HC concentration and smokiness were achieved. However, the NO_x and thermo-mechanical engine load increased.

  8. Angular-resolution and material-characterization measurements for a dual-particle imaging system with mixed-oxide fuel

    Energy Technology Data Exchange (ETDEWEB)

    Poitrasson-Rivière, Alexis, E-mail: alexispr@umich.edu [Department of Nuclear Engineering & Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Polack, J. Kyle; Hamel, Michael C.; Klemm, Dietrich D.; Ito, Kai; McSpaden, Alexander T.; Flaska, Marek; Clarke, Shaun D.; Pozzi, Sara A. [Department of Nuclear Engineering & Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Tomanin, Alice [Lainsa-Italia S.R.L., Via E. Fermi 2749, 21027 Ispra, VA (Italy); Peerani, Paolo [European Commission, Joint Research Centre, Institute for Transuranium Elements, 21027 Ispra, VA (Italy)

    2015-10-11

    A dual-particle imaging (DPI) system, capable of simultaneously imaging fast neutrons and gamma rays, has been operated in the presence of mixed-oxide (MOX) fuel to assess the system's angular resolution and material-characterization capabilities. The detection principle is based on the scattering physics of neutrons (elastic scattering) and gamma rays (Compton scattering) in organic and inorganic scintillators. The detection system is designed as a combination of a two-plane Compton camera and a neutron-scatter camera. The front plane consists of EJ-309 liquid scintillators and the back plane consists of interleaved EJ-309 and NaI(Tl) scintillators. MCNPX-PoliMi was used to optimize the geometry of the system and the resulting prototype was built and tested using a Cf-252 source as an SNM surrogate. A software package was developed to acquire and process data in real time. The software was used for a measurement campaign to assess the angular resolution of the imaging system with MOX samples. Measurements of two MOX canisters of similar isotopics and intensity were performed for 6 different canister separations (from 5° to 30°, corresponding to distances of 21 cm and 131 cm, respectively). The measurements yielded a minimum separation of 20° at 2.5 m (86-cm separation) required to see 2 separate hot spots. Additionally, the results displayed good agreement with MCNPX-PoliMi simulations. These results indicate an angular resolution between 15° and 20°, given the 5° step. Coupled with its large field of view, and its capability to differentiate between spontaneous fission and (α,n) sources, the DPI system shows its potential for nuclear-nonproliferation applications.

  9. CPFD simulations of an industrial-sized dual fluidized bed steam gasification system of biomass with 8 MW fuel input

    International Nuclear Information System (INIS)

    Kraft, Stephan; Kirnbauer, Friedrich; Hofbauer, Hermann

    2017-01-01

    Highlights: • We simulated an 8 MWth steam gasification system with the CPFD code Barracuda. • The prediction of the hydrodynamics depends strongly upon the chosen drag law. • The EMMS drag law predicted best the bed material recirculation and pressure drops. • The model of the DFB plant is able to predict the operation accurately. - Abstract: Dual fluidized bed (DFB) systems for biomass gasification consist of two connected fluidized beds with a circulating bed material in between. Inside such reactor systems, rough conditions occur due to the high temperatures and the movement of the bed material. Computational fluid dynamics calculations are a useful tool for investigating fluid dynamics inside such a reactor system. In this study, an industrial-sized DFB system was simulated with the commercial code CPFD Barracuda. The DFB system is part of the combined heat and power (CHP) plant at Güssing, situated in Austria, and has a total fuel input of 8 MW_t_h. The model was set up according to geometry and operating data which allows a realistic description of the hot system in the simulation environment. Furthermore, a conversion model for the biomass particles was implemented which covers the drying and devolatilization processes. Homogeneous and heterogeneous reactions were considered. Since drag models have an important influence on fluidization behavior, four drag models were tested. It was found that the EMMS drag model fits best, with an error of below 20%, whereas the other drag models produced much larger errors. Based on this drag law, further simulations were conducted. The simulation model correctly predicts the different fluidization regimes and pressure drops in the reactor system. It is also able to predict the compositions of the product and flue gas, as well as the temperatures inside the reactor, with reasonable accuracy. Due to the results obtained, Barracuda seems suitable for further investigations regarding the fluid mechanics of such

  10. Experimental investigation of hydrogen energy share improvement in a compression ignition engine using water injection and compression ratio reduction

    International Nuclear Information System (INIS)

    Chintala, V.; Subramanian, K.A.

    2016-01-01

    Highlights: • Energy efficiency (EE) increased with increase in hydrogen (H_2) energy share. • H_2 energy share increased from 19% to 79% with combined CR reduction and water. • In-cylinder temperature decreased significantly with water addition and CR reduction. • HC, CO, smoke and NO_x emissions with water and CR are lower than base diesel. - Abstract: This study deals with the effect of water addition on enhancement of maximum hydrogen energy share in a compression ignition engine (7.4 kW rated power at 1500 rpm) under dual fuel mode. The specific water consumption (SWC) was varied from 130 to 480 g/kW h in step of 70 g/kW h using manifold and port injection methods. Subsequently, the combined effect of reduction of compression ratio (CR) of the engine (from 19.5:1 (base) to 16.5:1 and 15.4:1) along with water addition on further enhancement of hydrogen energy share is investigated. The hydrogen energy share was limited to 18.8% with conventional dual fuel mode due to knocking. However, the energy share increased to 66.5% with water addition (maximum SWC: 480 g/kW h), and 79% with combined control strategies (SWC of 340 g/kW h and CR reduction to 16.5:1). Thermal efficiency of the engine under water added dual fuel mode is higher than base diesel mode (single fuel mode), but it is lower than the conventional dual fuel mode without water. The efficiency of the engine with reduced CR and water addition is lower than the conventional dual fuel mode, however at the CR of 16.5:1 and SWC of 340 g/kW h, the efficiency is comparable with base diesel mode efficiency. Hydrocarbon, carbon monoxide, smoke, and oxides of nitrogen emissions of the engine with water addition (340 g/kW h) and CR reduction (to 16.5:1) decreased significantly as compared to base diesel mode, but slightly higher than conventional dual fuel mode.

  11. Use of a single-zone thermodynamic model with detailed chemistry to study a natural gas fueled homogeneous charge compression ignition engine

    International Nuclear Information System (INIS)

    Zheng Junnian; Caton, Jerald A.

    2012-01-01

    Highlights: ► Auto-ignition characteristics of a natural gas fueled HCCI engine. ► Engine speed had the greatest effect on the auto-ignition process. ► Increases of C 2 H 6 or C 3 H 8 improved the auto-ignition process. ► Engine performance was not sensitive to small changes in C 2 H 6 or C 3 H 8 . ► Nitric oxides concentrations decreased as engine speed or EGR level was increased. - Abstract: A single zone thermodynamic model with detailed chemical kinetics was used to simulate a natural gas fueled homogeneous charge compression ignition (HCCI) engine. The model employed Chemkin and used chemical kinetics for natural gas with 53 species and 325 reactions. This simulation was used to complete analyses for a modified 0.4 L single cylinder engine. The engine possessed a compression ratio of 21.5:1, and had a bore and stroke of 86 and 75 mm, respectively. Several sets of parametric studies were completed to investigate the minimal initial temperature, engine performance, and nitric oxide emissions of HCCI engine operation. The results show significant changes in combustion characteristics with varying engine operating conditions. Effects of varying equivalence ratios (0.3–1.0), engine speeds (1000–4000 RPM), EGR (0–40%), and fuel compositions were determined and analyzed in detail. In particular, every 0.1 increase in equivalence ratio or 500 rpm increase in engine speed requires about a 5 K higher initial temperature for complete combustion, and leads to around 0.7 bar increase in IMEP.

  12. Investigating the reactivity controlled compression ignition (RCCI) combustion strategy in a natural gas/diesel fueled engine with a pre-chamber

    International Nuclear Information System (INIS)

    Salahi, Mohammad Mahdi; Esfahanian, Vahid; Gharehghani, Ayatallah; Mirsalim, Mostafa

    2017-01-01

    Highlights: • A novel combustion strategy, RCCI with a pre-chamber, is proposed and investigated. • The proposed strategy extends the RCCI operating range to use less intake air temperatures. • The new concept extends the RCCI operating range to use lower portions of the active fuel. • The proposed strategy is sensitive to engine load and is more efficient for high loads. - Abstract: Reactivity controlled compression ignition (RCCI) concept has been proven to be a promising combustion mode for the next generations of internal combustion engines. This strategy is still subject of extensive studies to overcome its operational limitations. In the present work, the effect of using a pre-chamber to extend some operating ranges in a RCCI engine is investigated using coupled multidimensional computational fluid dynamics (CFD) with detailed chemical kinetic mechanisms. To accomplish this, the combustion and flow field in a single cylinder engine with a pre-chamber, working in RCCI mode and fueled with natural gas/diesel are numerically modeled. Experimental data is used to validate the simulation results and then, combustion characteristics and engine emissions in some various operating regions, in terms of initial temperature, fuel equivalence ratio and portions of the two fuels are discussed. The results reveal that the proposed strategy provides the ability to extend the engine operating ranges to use lower intake temperatures, even to 50 K lower for some cases, and also using a larger portion of natural gas instead of diesel fuel. On the other hand, the new strategy could result in incomplete combustion and formation of related emissions in low loads, but for higher engine loads it shows better combustion characteristics.

  13. Emissions of toxic pollutants from compressed natural gas and low sulfur diesel-fueled heavy-duty transit buses tested over multiple driving cycles.

    Science.gov (United States)

    Kado, Norman Y; Okamoto, Robert A; Kuzmicky, Paul A; Kobayashi, Reiko; Ayala, Alberto; Gebel, Michael E; Rieger, Paul L; Maddox, Christine; Zafonte, Leo

    2005-10-01

    The number of heavy-duty vehicles using alternative fuels such as compressed natural gas (CNG) and new low-sulfur diesel fuel formulations and equipped with after-treatment devices are projected to increase. However, few peer-reviewed studies have characterized the emissions of particulate matter (PM) and other toxic compounds from these vehicles. In this study, chemical and biological analyses were used to characterize the identifiable toxic air pollutants emitted from both CNG and low-sulfur-diesel-fueled heavy-duty transit buses tested on a chassis dynamometer over three transient driving cycles and a steady-state cruise condition. The CNG bus had no after-treatment, and the diesel bus was tested first equipped with an oxidation catalyst (OC) and then with a catalyzed diesel particulate filter (DPF). Emissions were analyzed for PM, volatile organic compounds (VOCs; determined on-site), polycyclic aromatic hydrocarbons (PAHs), and mutagenic activity. The 2000 model year CNG-fueled vehicle had the highest emissions of 1,3-butadiene, benzene, and carbonyls (e.g., formaldehyde) of the three vehicle configurations tested in this study. The 1998 model year diesel bus equipped with an OC and fueled with low-sulfur diesel had the highest emission rates of PM and PAHs. The highest specific mutagenic activities (revertants/microg PM, or potency) and the highest mutagen emission rates (revertants/mi) were from the CNG bus in strain TA98 tested over the New York Bus (NYB) driving cycle. The 1998 model year diesel bus with DPF had the lowest VOCs, PAH, and mutagenic activity emission. In general, the NYB driving cycle had the highest emission rates (g/mi), and the Urban Dynamometer Driving Schedule (UDDS) had the lowest emission rates for all toxics tested over the three transient test cycles investigated. Also, transient emissions were, in general, higher than steady-state emissions. The emissions of toxic compounds from an in-use CNG transit bus (without an oxidation

  14. Modeling of heat release and emissions from droplet combustion of multi component fuels in compression ignition engines

    DEFF Research Database (Denmark)

    Ivarsson, Anders

    emissions from the compression ignition engines (CI engines or diesel engines) are continuously increased. To comply with this, better modeling tools for the diesel combustion process are desired from the engine developers. The complex combustion process of a compression ignition engine may be divided...... it is well suited for optical line of sight diagnostics in both pre and post combustion regions. The work also includes some preliminary studies of radiant emissions from helium stabilized ethylene/air and methane/oxygen flames. It is demonstrated that nano particles below the sooting threshold actually...... of ethylene/air flames well known from the experimental work, was used for the model validation. Two cases were helium stabilized flames with φ = 1 and 2.14. The third case was an unstable flame with φ = 2.14. The unstable case was used to test whether a transient model would be able to predict the frequency...

  15. Study of alcohol fuel of butanol and ethanol effect on the compression ignition (CI) engine performance, combustion and emission characteristic

    Science.gov (United States)

    Aziz, M. A.; Yusop, A. F.; Mat Yasin, M. H.; Hamidi, M. A.; Alias, A.; Hussin, H.; Hamri, S.

    2017-10-01

    Diesel engine which is one of the larger contributors to total consumption for petroleum is an attractive power unit used widely in many fields. However, diesel engines are among the main contributors to air pollutions for the large amount of emissions, such as CO, CO2 and NOx lead to an adverse effect on human health. Many researches have been done to find alternative fuels that are clean and efficient. Biodiesel is preferred as an alternative source for diesel engine which produces lower emission of pollutants. This study has focused on the evaluation of diesel and alcohol-diesel fuel properties and also the performance, combustion and exhaust emission from diesel engine fuelled with diesel and alcohol. Butanol and ethanol is blend with diesel fuel at 1:9 ratio. There are three test fuel that is tested which Diesel (100% diesel), D90BU10 (10% Butanol and 90% diesel) and D90E10 (10% Ethanol and 90% diesel). The comparison between diesel and alcohol-diesel blend has been made in terms of fuel properties characterization, engine performance such as brake power (BP) and brake specific fuel consumption (BSFC) also the in cylinder maximum pressure characteristic. Thus, exhaust gas emission of CO, CO2, NOx and O2 emission also has been observed at constant load of 50% but in different operating engine speed (1100 rpm, 1400 rpm, 1700 rpm, 2000 rpm and 2300 rpm). The results show the addition of 10% of each butanol and ethanol to diesel fuel had decreased the fuel density about 0.3% to 0.5% compared to mineral diesel. In addition, viscosity and energy content are also decrease. The addition of 10% butanol had improved the fuel cetane number however the ethanol blends react differently. In term of engine performance, as the engine speed increased, BP output also increase respectively. Hence, the alcohol blends fuel generates lower BP compared to diesel, plus BSFC for all test fuel shows decreasing trend at low and medium speed, however increased gradually at higher engine

  16. Effects of antioxidant additives on exhaust emissions reduction in compression ignition engine fueled with methyl ester of annona oil

    Directory of Open Access Journals (Sweden)

    Ramalingam Senthil

    2016-01-01

    Full Text Available In this present study, biodiesel is a cleaner burning alternative fuel to the Neat diesel fuel. However, several studies are pointed out that increase in NOx emission for biodiesel when compared with the Neat diesel fuel. The aim of the present study is to analyze the effect of antioxidant (p-phenylenediamine on engine emissions of a Diesel engine fuelled with methyl ester of annona oil. The antioxidant is mixed in various concentrations (0.010 to 0.040% (w/w with methyl ester of annona oil. Result shows that antioxidant additive mixture (MEAO+P200 is effective in control of NOx and HC emission of methyl ester of annona oil fuelled engine without doing any engine modification.

  17. Neutronics optimization of LiPb-He dual-cooled fuel breeding blanket for the fusion-driven sub-critical system

    International Nuclear Information System (INIS)

    Zheng Shanliang; Wu Yican

    2002-01-01

    The concept of the liquid Li 17 Pb 83 and Helium gas dual-cooled Fuel Breeding Blanket (FBB) for the Fusion-Driven sub-critical System (FDS) is presented and analyzed. Taking self-sustaining tritium (TBR > 1.05) and annual output of 100 kg or more fissile 239 Pu (FBR > 0.238) as objective parameters, and based on the three-dimensional Monte Carlo neutron-photon transport code MCNP/4A, a neutronics-optimized calculation of different cases was carried out and the concept is proved feasible. In addition, the total breeding ratio (Br = Tbr + Fbr) is listed corresponding to different cases

  18. Experimental study on the natural gas dual fuel engine test and the higher the mixture ratio of hydrogen to natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B.S.; Lee, Y.S.; Park, C.K. [Cheonnam University, Kwangju (Korea); Masahiro, S. [Kyoto University, Kyoto (Japan)

    1999-05-28

    One of the unsolved problems of the natural gas dual fuel engine is that there is too much exhaust of Total Hydrogen Carbon(THC) at a low equivalent mixture ratio. To fix it, a natural gas mixed with hydrogen was applied to engine test. The results showed that the higher the mixture ratio of hydrogen to natural gas, the higher the combustion efficiency. And when the amount of the intake air is reached to 90% of WOT, the combustion efficiency was promoted. But, like a case making the injection timing earlier, the equivalent mixture ratio for the nocking limit decreases and the produce of NOx increases. 5 refs., 9 figs., 1 tab.

  19. Overview of the Safety Issues Associated with the Compressed Natural Gas Fuel System and Electric Drive System in a Heavy Hybrid Electric Vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, S.C.

    2002-11-14

    This report evaluates the hazards that are unique to a compressed-natural-gas (CNG)-fueled heavy hybrid electric vehicle (HEV) design compared with a conventional heavy vehicle. The unique design features of the heavy HEV are the CNG fuel system for the internal-combustion engine (ICE) and the electric drive system. This report addresses safety issues with the CNG fuel system and the electric drive system. Vehicles on U. S. highways have been propelled by ICEs for several decades. Heavy-duty vehicles have typically been fueled by diesel fuel, and light-duty vehicles have been fueled by gasoline. The hazards and risks posed by ICE vehicles are well understood and have been generally accepted by the public. The economy, durability, and safety of ICE vehicles have established a standard for other types of vehicles. Heavy-duty (i.e., heavy) HEVs have recently been introduced to U. S. roadways, and the hazards posed by these heavy HEVs can be compared with the hazards posed by ICE vehicles. The benefits of heavy HEV technology are based on their potential for reduced fuel consumption and lower exhaust emissions, while the disadvantages are the higher acquisition cost and the expected higher maintenance costs (i.e., battery packs). The heavy HEV is more suited for an urban drive cycle with stop-and-go driving conditions than for steady expressway speeds. With increasing highway congestion and the resulting increased idle time, the fuel consumption advantage for heavy HEVs (compared with conventional heavy vehicles) is enhanced by the HEVs' ability to shut down. Any increase in fuel cost obviously improves the economics of a heavy HEV. The propulsion system for a heavy HEV is more complex than the propulsion system for a conventional heavy vehicle. The heavy HEV evaluated in this study has in effect two propulsion systems: an ICE fueled by CNG and an electric drive system with additional complexity and failure modes. This additional equipment will result in a less

  20. Toxicological properties of emission particles from heavy duty engines powered by conventional and bio-based diesel fuels and compressed natural gas.

    Science.gov (United States)

    Jalava, Pasi I; Aakko-Saksa, Päivi; Murtonen, Timo; Happo, Mikko S; Markkanen, Ari; Yli-Pirilä, Pasi; Hakulinen, Pasi; Hillamo, Risto; Mäki-Paakkanen, Jorma; Salonen, Raimo O; Jokiniemi, Jorma; Hirvonen, Maija-Riitta

    2012-09-29

    One of the major areas for increasing the use of renewable energy is in traffic fuels e.g. bio-based fuels in diesel engines especially in commuter traffic. Exhaust emissions from fossil diesel fuelled engines are known to cause adverse effects on human health, but there is very limited information available on how the new renewable fuels may change the harmfulness of the emissions, especially particles (PM). We evaluated the PM emissions from a heavy-duty EURO IV diesel engine powered by three different fuels; the toxicological properties of the emitted PM were investigated. Conventional diesel fuel (EN590) and two biodiesels were used - rapeseed methyl ester (RME, EN14214) and hydrotreated vegetable oil (HVO) either as such or as 30% blends with EN590. EN590 and 100% HVO were also operated with or without an oxidative catalyst (DOC + POC). A bus powered by compressed natural gas (CNG) was included for comparison with the liquid fuels. However, the results from CNG powered bus cannot be directly compared to the other situations in this study. High volume PM samples were collected on PTFE filters from a constant volume dilution tunnel. The PM mass emission with HVO was smaller and with RME larger than that with EN590, but both biofuels produced lower PAH contents in emission PM. The DOC + POC catalyst greatly reduced the PM emission and PAH content in PM with both HVO and EN590. Dose-dependent TNFα and MIP-2 responses to all PM samples were mostly at the low or moderate level after 24-hour exposure in a mouse macrophage cell line RAW 264.7. Emission PM from situations with the smallest mass emissions (HVO + cat and CNG) displayed the strongest potency in MIP-2 production. The catalyst slightly decreased the PM-induced TNFα responses and somewhat increased the MIP-2 responses with HVO fuel. Emission PM with EN590 and with 30% HVO blended in EN590 induced the strongest genotoxic responses, which were significantly greater than those with EN590

  1. Study of the hoop fracture behaviour of nuclear fuel cladding from ring compression tests by means of non-linear optimization techniques

    Energy Technology Data Exchange (ETDEWEB)

    Gómez, F.J., E-mail: javier.gomez@amsimulation.com [Advanced Material Simulation, AMS, Bilbao (Spain); Martin Rengel, M.A., E-mail: mamartin.rengel@upm.es [E.T.S.I. Caminos, Canales y Puertos, Universidad Politécnica de Madrid, C/Professor Aranguren SN, E-28040 Madrid (Spain); Ruiz-Hervias, J.; Puerta, M.A. [E.T.S.I. Caminos, Canales y Puertos, Universidad Politécnica de Madrid, C/Professor Aranguren SN, E-28040 Madrid (Spain)

    2017-06-15

    In this work, the hoop fracture toughness of ZIRLO{sup ®} fuel cladding is calculated as a function of three parameters: hydrogen concentration, temperature and displacement rate. To this end, pre-hydrided samples with nominal hydrogen concentrations of 0 (as-received), 150, 250, 500, 1200 and 2000 ppm were prepared. Hydrogen was precipitated as zirconium hydrides in the shape of platelets oriented along the hoop direction. Ring Compression Tests (RCTs) were conducted at three temperatures (20, 135 and 300 °C) and two displacement rates (0.5 and 100 mm/min). A new method has been proposed in this paper which allows the determination of fracture toughness from ring compression tests. The proposed method combines the experimental results, the cohesive crack model, finite elements simulations, numerical calculations and non-linear optimization techniques. The parameters of the cohesive crack model were calculated by minimizing the difference between the experimental data and the numerical results. An almost perfect fitting of the experimental results is achieved by this method. In addition, an estimation of the error in the calculated fracture toughness is also provided.

  2. Verification of the FBR fuel bundle-duct interaction analysis code BAMBOO by the out-of-pile bundle compression test with large diameter pins

    Science.gov (United States)

    Uwaba, Tomoyuki; Ito, Masahiro; Nemoto, Junichi; Ichikawa, Shoichi; Katsuyama, Kozo

    2014-09-01

    The BAMBOO computer code was verified by results for the out-of-pile bundle compression test with large diameter pin bundle deformation under the bundle-duct interaction (BDI) condition. The pin diameters of the examined test bundles were 8.5 mm and 10.4 mm, which are targeted as preliminary fuel pin diameters for the upgraded core of the prototype fast breeder reactor (FBR) and for demonstration and commercial FBRs studied in the FaCT project. In the bundle compression test, bundle cross-sectional views were obtained from X-ray computer tomography (CT) images and local parameters of bundle deformation such as pin-to-duct and pin-to-pin clearances were measured by CT image analyses. In the verification, calculation results of bundle deformation obtained by the BAMBOO code analyses were compared with the experimental results from the CT image analyses. The comparison showed that the BAMBOO code reasonably predicts deformation of large diameter pin bundles under the BDI condition by assuming that pin bowing and cladding oval distortion are the major deformation mechanisms, the same as in the case of small diameter pin bundles. In addition, the BAMBOO analysis results confirmed that cladding oval distortion effectively suppresses BDI in large diameter pin bundles as well as in small diameter pin bundles.

  3. Verification of the FBR fuel bundle–duct interaction analysis code BAMBOO by the out-of-pile bundle compression test with large diameter pins

    Energy Technology Data Exchange (ETDEWEB)

    Uwaba, Tomoyuki, E-mail: uwaba.tomoyuki@jaea.go.jp [Japan Atomic Energy Agency, 4002, Narita-cho, Oarai-machi, Ibaraki 311-1393 (Japan); Ito, Masahiro; Nemoto, Junichi [Japan Atomic Energy Agency, 4002, Narita-cho, Oarai-machi, Ibaraki 311-1393 (Japan); Ichikawa, Shoichi [Japan Atomic Energy Agency, 2-1, Shiraki, Tsuruga-shi, Fukui 919-1279 (Japan); Katsuyama, Kozo [Japan Atomic Energy Agency, 4002, Narita-cho, Oarai-machi, Ibaraki 311-1393 (Japan)

    2014-09-15

    The BAMBOO computer code was verified by results for the out-of-pile bundle compression test with large diameter pin bundle deformation under the bundle–duct interaction (BDI) condition. The pin diameters of the examined test bundles were 8.5 mm and 10.4 mm, which are targeted as preliminary fuel pin diameters for the upgraded core of the prototype fast breeder reactor (FBR) and for demonstration and commercial FBRs studied in the FaCT project. In the bundle compression test, bundle cross-sectional views were obtained from X-ray computer tomography (CT) images and local parameters of bundle deformation such as pin-to-duct and pin-to-pin clearances were measured by CT image analyses. In the verification, calculation results of bundle deformation obtained by the BAMBOO code analyses were compared with the experimental results from the CT image analyses. The comparison showed that the BAMBOO code reasonably predicts deformation of large diameter pin bundles under the BDI condition by assuming that pin bowing and cladding oval distortion are the major deformation mechanisms, the same as in the case of small diameter pin bundles. In addition, the BAMBOO analysis results confirmed that cladding oval distortion effectively suppresses BDI in large diameter pin bundles as well as in small diameter pin bundles.

  4. The Effect of Variation of Molarity of Alkali Activator and Fine Aggregate Content on the Compressive Strength of the Fly Ash: Palm Oil Fuel Ash Based Geopolymer Mortar

    Directory of Open Access Journals (Sweden)

    Iftekhair Ibnul Bashar

    2014-01-01

    Full Text Available The effect of molarity of alkali activator, manufactured sand (M-sand, and quarry dust (QD on the compressive strength of palm oil fuel ash (POFA and fly ash (FA based geopolymer mortar was investigated and reported. The variable investigated includes the quantities of replacement levels of M-sand, QD, and conventional mining sand (N-sand in two concentrated alkaline solutions; the contents of alkaline solution, water, POFA/FA ratio, and curing condition remained constant. The results show that an average of 76% of the 28-day compressive strength was found at the age of 3 days. The rate of strength development from 3 to 7 days was found between 12 and 16% and it was found much less beyond this period. The addition of 100% M-sand and QD shows insignificant strength reduction compared to mixtures with 100% N-sand. The particle angularity and texture of fine aggregates played a significant role in the strength development due to the filling and packing ability. The rough texture and surface of QD enables stronger bond between the paste and the fine aggregate. The concentration of alkaline solution increased the reaction rate and thus enhanced the development of early age strength. The use of M-sand and QD in the development of geopolymer concrete is recommended as the strength variation between these waste materials and conventional sand is not high.

  5. Fabrication of carbon-polymer composite bipolar plates for polymer electrolyte membrane fuel cells by compression moulding

    International Nuclear Information System (INIS)

    Raza, M.A.; Ahmed, R.; Saleem, A.; Din, R.U.

    2009-01-01

    Fuel cells are considered as one of the most important technologies to address the future energy and environmental pollution problems. These are the most promising power sources for road transportation and portable devices. A fuel cell is an electrochemical device that converts chemical energy into electrical energy. A fuel cell stack consists of bipolar plates and membrane electrode assemblies (MEA). The bipolar plate is by weight, volume and cost one of the most significant components of a fuel cell stack. Major functions of bipolar plates are to separate oxidant and fuel gas, provide flow channels, conduct electricity and provide heat transfer. Bipolar plates can be made from various materials including graphite, metals, carbon / carbon and carbon/ polymer composites. Materials for carbon-polymer composites are relatively inexpensive, less corrosive, strong and channels can be formed by means of a moulding process. Carbon-polymer composites are of two type i.e; thermosetting and thermoplastic. For thermosetting composite a bulk molding compound (BMC) was prepared by adding graphite, vinyl ester resin, methyl ethyl ketone peroxide and cobalt naphthalate. The BMC was thoroughly mixed, poured into a die mould of a bipolar plate with channels and hot pressed at a specific temperature and pressure. A bipolar plate was formed according to the die mould. Design of the mould is also discussed. Conducting polymers were also added to BMC to increase the conductivity of bipolar plates. Particle size of the graphite has also a significant effect on the conductivity of the bipolar plates. Thermoplastic composites were also prepared using polypropylene and graphite.

  6. Decreasing the emissions of a partially premixed gasoline fueled compression ignition engine by means of injection characteristics and EGR

    Directory of Open Access Journals (Sweden)

    Nemati Arash

    2011-01-01

    Full Text Available This paper is presented in order to elucidate some numerical investigations related to a partially premixed gasoline fuelled engine by means of three dimensional CFD code. Comparing with the diesel fuel, gasoline has lower soot emission because of its higher ignition delay. The application of double injection strategy reduces the maximum heat release rate and leads to the reduction of NOx emission. For validation of the model, the results for the mean in-cylinder pressure, H.R.R., NOx and soot emissions are compared with the corresponding experimental data and show good levels of agreement. The effects of injection characteristics such as, injection duration, spray angle, nozzle hole diameter, injected fuel temperature and EGR rate on combustion process and emission formation are investigated yielding the determination of the optimal point thereafter. The results indicated that optimization of injection characteristics leads to simultaneous reduction of NOx and soot emissions with negligible change in IMEP.

  7. On the effect of injection timing on the ignition of lean PRF/air/EGR mixtures under direct dual fuel stratification conditions

    KAUST Repository

    Luong, Minh Bau; Sankaran, Ramanan; Yu, Gwang Hyeon; Chung, Suk-Ho; Yoo, Chun Sang

    2017-01-01

    The ignition characteristics of lean primary reference fuel (PRF)/air/exhaust gas recirculation (EGR) mixture under reactivity-controlled compression ignition (RCCI) and direct duel fuel stratification (DDFS) conditions are investigated by 2-D direct numerical simulations (DNSs) with a 116-species reduced chemistry of the PRF oxidation. The 2-D DNSs of the DDFS combustion are performed by varying the injection timing of iso-octane (i-C8H18) with a pseudo-iso-octane (PC8H18) model together with a novel compression heating model to account for the compression heating and expansion cooling effects of the piston motion in an engine cylinder. The PC8H18 model is newly developed to mimic the timing, duration, and cooling effects of the direct injection of i-C8H18 onto a premixed background charge of PRF/air/EGR mixture with composition inhomogeneities. It is found that the RCCI combustion exhibits a very high peak heat release rate (HRR) with a short combustion duration due to the predominance of the spontaneous ignition mode of combustion. However, the DDFS combustion has much lower peak HRR and longer combustion duration regardless of the fuel injection timing compared to those of the RCCI combustion, which is primarily attributed to the sequential injection of i-C8H18. It is also found that the ignition delay of the DDFS combustion features a non-monotonic behavior with increasing fuel-injection timing due to the different effect of fuel evaporation on the low-, intermediate-, and high-temperature chemistry of the PRF oxidation. The budget and Damköhler number analyses verify that although a mixed combustion mode of deflagration and spontaneous ignition exists during the early phase of the DDFS combustion, the spontaneous ignition becomes predominant during the main combustion, and hence, the spread-out of heat release rate in the DDFS combustion is mainly governed by the direct injection process of i-C8H18. Finally, a misfire is observed for the DDFS combustion when

  8. On the effect of injection timing on the ignition of lean PRF/air/EGR mixtures under direct dual fuel stratification conditions

    KAUST Repository

    Luong, Minh Bau

    2017-06-10

    The ignition characteristics of lean primary reference fuel (PRF)/air/exhaust gas recirculation (EGR) mixture under reactivity-controlled compression ignition (RCCI) and direct duel fuel stratification (DDFS) conditions are investigated by 2-D direct numerical simulations (DNSs) with a 116-species reduced chemistry of the PRF oxidation. The 2-D DNSs of the DDFS combustion are performed by varying the injection timing of iso-octane (i-C8H18) with a pseudo-iso-octane (PC8H18) model together with a novel compression heating model to account for the compression heating and expansion cooling effects of the piston motion in an engine cylinder. The PC8H18 model is newly developed to mimic the timing, duration, and cooling effects of the direct injection of i-C8H18 onto a premixed background charge of PRF/air/EGR mixture with composition inhomogeneities. It is found that the RCCI combustion exhibits a very high peak heat release rate (HRR) with a short combustion duration due to the predominance of the spontaneous ignition mode of combustion. However, the DDFS combustion has much lower peak HRR and longer combustion duration regardless of the fuel injection timing compared to those of the RCCI combustion, which is primarily attributed to the sequential injection of i-C8H18. It is also found that the ignition delay of the DDFS combustion features a non-monotonic behavior with increasing fuel-injection timing due to the different effect of fuel evaporation on the low-, intermediate-, and high-temperature chemistry of the PRF oxidation. The budget and Damköhler number analyses verify that although a mixed combustion mode of deflagration and spontaneous ignition exists during the early phase of the DDFS combustion, the spontaneous ignition becomes predominant during the main combustion, and hence, the spread-out of heat release rate in the DDFS combustion is mainly governed by the direct injection process of i-C8H18. Finally, a misfire is observed for the DDFS combustion when

  9. Coal-fuelled systems for peaking power with 100% CO2 capture through integration of solid oxide fuel cells with compressed air energy storage

    Science.gov (United States)

    Nease, Jake; Adams, Thomas A.

    2014-04-01

    In this study, a coal-fuelled integrated solid oxide fuel cell (SOFC) and compressed air energy storage (CAES) system in a load-following power production scenario is discussed. Sixteen SOFC-based plants with optional carbon capture and sequestration (CCS) and syngas shifting steps are simulated and compared to a state-of-the-art supercritical pulverised coal (SCPC) plant. Simulations are performed using a combination of MATLAB and Aspen Plus v7.3. It was found that adding CAES to a SOFC-based plant can provide load-following capabilities with relatively small effects on efficiencies (1-2% HHV depending on the system configuration) and levelized costs of electricity (∼0.35 ¢ kW-1 h-1). The load-following capabilities, as measured by least-squares metrics, show that this system may utilize coal and achieve excellent load-tracking that is not adversely affected by the inclusion of CCS. Adding CCS to the SOFC/CAES system reduces measurable direct CO2 emission to zero. A seasonal partial plant shutdown schedule is found to reduce fuel consumption by 9.5% while allowing for cleaning and maintenance windows for the SOFC stacks without significantly affecting the performance of the system (∼1% HHV reduction in efficiency). The SOFC-based systems with CCS are found to become economically attractive relative to SCPC above carbon taxes of 22 ton-1.

  10. The Bacterial Flagellar Type III Export Gate Complex Is a Dual Fuel Engine That Can Use Both H+ and Na+ for Flagellar Protein Export.

    Directory of Open Access Journals (Sweden)

    Tohru Minamino

    2016-03-01

    Full Text Available The bacterial flagellar type III export apparatus utilizes ATP and proton motive force (PMF to transport flagellar proteins to the distal end of the growing flagellar structure for self-assembly. The transmembrane export gate complex is a H+-protein antiporter, of which activity is greatly augmented by an associated cytoplasmic ATPase complex. Here, we report that the export gate complex can use sodium motive force (SMF in addition to PMF across the cytoplasmic membrane to drive protein export. Protein export was considerably reduced in the absence of the ATPase complex and a pH gradient across the membrane, but Na+ increased it dramatically. Phenamil, a blocker of Na+ translocation, inhibited protein export. Overexpression of FlhA increased the intracellular Na+ concentration in the presence of 100 mM NaCl but not in its absence, suggesting that FlhA acts as a Na+ channel. In wild-type cells, however, neither Na+ nor phenamil affected protein export, indicating that the Na+ channel activity of FlhA is suppressed by the ATPase complex. We propose that the export gate by itself is a dual fuel engine that uses both PMF and SMF for protein export and that the ATPase complex switches this dual fuel engine into a PMF-driven export machinery to become much more robust against environmental changes in external pH and Na+ concentration.

  11. The Bacterial Flagellar Type III Export Gate Complex Is a Dual Fuel Engine That Can Use Both H+ and Na+ for Flagellar Protein Export.

    Science.gov (United States)

    Minamino, Tohru; Morimoto, Yusuke V; Hara, Noritaka; Aldridge, Phillip D; Namba, Keiichi

    2016-03-01

    The bacterial flagellar type III export apparatus utilizes ATP and proton motive force (PMF) to transport flagellar proteins to the distal end of the growing flagellar structure for self-assembly. The transmembrane export gate complex is a H+-protein antiporter, of which activity is greatly augmented by an associated cytoplasmic ATPase complex. Here, we report that the export gate complex can use sodium motive force (SMF) in addition to PMF across the cytoplasmic membrane to drive protein export. Protein export was considerably reduced in the absence of the ATPase complex and a pH gradient across the membrane, but Na+ increased it dramatically. Phenamil, a blocker of Na+ translocation, inhibited protein export. Overexpression of FlhA increased the intracellular Na+ concentration in the presence of 100 mM NaCl but not in its absence, suggesting that FlhA acts as a Na+ channel. In wild-type cells, however, neither Na+ nor phenamil affected protein export, indicating that the Na+ channel activity of FlhA is suppressed by the ATPase complex. We propose that the export gate by itself is a dual fuel engine that uses both PMF and SMF for protein export and that the ATPase complex switches this dual fuel engine into a PMF-driven export machinery to become much more robust against environmental changes in external pH and Na+ concentration.

  12. Microgeneration of electricity with producer gas in dual fuel mode operation Microgeração de eletricidade com gás de gaseificação num motor gerador dual

    Directory of Open Access Journals (Sweden)

    Marcelo J. Silva

    2011-10-01

    Full Text Available Among the alternatives to meet the increasing of world demand for energy, the use of biomass as energy source is one of the most promising as it contributes to reducing emissions of carbon dioxide in the atmosphere. Gasification is a technological process of biomass energy production of a gaseous biofuel. The fuel gas has a low calorific value that can be used in Diesel engine in dual mode for power generation in isolated communities. This study aimed to evaluate the reduction in the consumption of oil Diesel an engine generator, using gas from gasification of wood. The engine generator brand used was a BRANCO, with direct injection power of 7.36 kW (10 HP coupled to an electric generator 5.5 kW. Diesel oil mixed with intake air was injected, as the oil was injected via an injector of the engine (dual mode. The fuel gas was produced in a downdraft gasifier. The engine generator was put on load system from 0.5 kW to 3.5 kW through a set of electrical resistances. Diesel oil consumption was measured with a precision scale. It was concluded that the engine converted to dual mode when using the gas for the gasification of wood decreased Diesel consumption by up to 57%.Dentre as alternativas à crescente demanda energética mundial, o uso da biomassa como fonte de energia é uma das formas mais promissoras, pois contribui para a redução das emissões de dióxido de carbono na atmosfera. A gaseificação é uma tecnologia de transformação energética da biomassa num biocombustível gasoso. O gás de gaseificação é um combustível de baixo poder calorífico que pode ser utilizado em motor ciclo Diesel no modo dual para geração de energia elétrica em comunidades isoladas. Este trabalho teve por objetivo avaliar a redução no consumo de Diesel num motor gerador, com a utilização de gás da gaseificação da madeira. O motor avaliado foi da marca BRANCO, com injeção direta e potência de 7,36 kW (10 cv acoplado a um gerador elétrico de 5

  13. Combustion characteristics of lemongrass (Cymbopogon flexuosus oil in a partial premixed charge compression ignition engine

    Directory of Open Access Journals (Sweden)

    Avinash Alagumalai

    2015-09-01

    Full Text Available Indeed, the development of alternate fuels for use in internal combustion engines has traditionally been an evolutionary process in which fuel-related problems are met and critical fuel properties are identified and their specific limits defined to resolve the problem. In this regard, this research outlines a vision of lemongrass oil combustion characteristics. In a nut-shell, the combustion phenomena of lemongrass oil were investigated at engine speed of 1500 rpm and compression ratio of 17.5 in a 4-stroke cycle compression ignition engine. Furthermore, the engine tests were conducted with partial premixed charge compression ignition-direct injection (PCCI-DI dual fuel system to profoundly address the combustion phenomena. Analysis of cylinder pressure data and heat-release analysis of neat and premixed lemongrass oil were demonstrated in-detail and compared with conventional diesel. The experimental outcomes disclosed that successful ignition and energy release trends can be obtained from a compression ignition engine fueled with lemongrass oil.

  14. Numerical investigation to the dual-fuel spray combustion process in an ethanol direct injection plus gasoline port injection (EDI + GPI) engine

    International Nuclear Information System (INIS)

    Huang, Yuhan; Hong, Guang; Huang, Ronghua

    2015-01-01

    Highlights: • A 5D PDF table was used to model the dual-fuel turbulence–chemistry interactions. • The cooling effect of ethanol direct injection (EDI) was examined. • The higher flame speed of ethanol in EDI + GPI increased the thermal efficiency. • The partially premixed combustion in EDI + GPI reduced the combustion temperature. • Ethanol’s low evaporation rate in low temperature led to incomplete combustion. - Abstract: Ethanol direct injection plus gasoline port injection (EDI + GPI) is a new technology to make the use of ethanol fuel more effective and efficient in spark ignition engines. Multi-dimensional computational fluid dynamics modelling was conducted on an EDI + GPI engine in both single and dual fuelled conditions. The in-cylinder flow field was solved in the realizable k−ε turbulence model with detailed engine geometry. The temporal and spatial distributions of the liquid and vapour fuels were simulated with the spray breakup and evaporation models. The combustion process was modelled with the partially premixed combustion concept in which both mixture fraction and progress variable were solved. The three-dimensional and five-dimensional presumed Probability Density Function (PDF) look-up tables were used to model the single-fraction-mixture and two-fraction-mixture turbulence–chemistry interactions respectively. The model was verified by comparing the numerical and experimental results of spray pattern and cylinder pressure. The simulation results showed that the combustion process of EDI + GPI dual-fuelled condition was partially premixed combustion because of the low evaporation rate of ethanol spray in low temperature environment before combustion. Compared with GPI only, the higher flame speed of ethanol fuel contributed to the greater pressure rise rate and maximum cylinder pressure in EDI + GPI condition, which consequently resulted in higher power output and thermal efficiency. The lower adiabatic flame temperature of

  15. Performance and combustion analysis of Mahua biodiesel on a single cylinder compression ignition engine using electronic fuel injection system

    Directory of Open Access Journals (Sweden)

    Gunasekaran Anandkumar

    2016-01-01

    Full Text Available In this investigation, experiment is carried out on a 1500 rpm constant speed single cylinder Diesel engine. The test is carried out with Neat diesel, neat biodiesel, and blend B20. The engine considered was run with electronic fuel injection system supported by common rail direct injection to obtain high atomization and effective air utilization inside the combustion chamber. The performance of the engine in terms of break thermal efficiency and brake specific energy consumption was found and compared. The B20 blend shows 1.11% decrease in break thermal efficiency and 3.35% increase in brake specific energy consumption than diesel. The combustion characteristics found are in-cylinder pressure, rate of pressure rise, and heat release rate and compared for peak pressure load to understand the nature of combustion process. For each fuel test run, the maximum peak pressure is observed at part load condition. The rate of change of pressure and heat release rate of diesel is high compared to pure biodiesel and B20 blend. The diffusion combustion is observed to be predominant in case of B100 than B20 and Neat diesel.

  16. Assessment of air quality after the implementation of compressed natural gas (CNG) as fuel in public transport in Delhi, India.

    Science.gov (United States)

    Ravindra, Khaiwal; Wauters, Eric; Tyagi, Sushil K; Mor, Suman; Van Grieken, René

    2006-04-01

    Public transport in Delhi was amended by the Supreme Court of India to use Compressed Natural Gas (CNG) instead of diesel or petrol. After the implementation of CNG since April 2001, Delhi has the highest fraction of CNG-run public vehicles in the world and most of them were introduced within 20 months. In the present study, the concentrations of various criteria air pollutants (SPM, PM(10), CO, SO(2) and NO(x)) and organic pollutants such as benzene, toluene, xylene (BTX) and polycyclic aromatic hydrocarbons (PAHs) were assessed before and after the implementation of CNG. A decreasing trend was found for PAHs, SO(2) and CO concentrations, while the NO(x) level was increased in comparison to those before the implementation of CNG. Further, SPM, PM(10), and BTX concentrations showed no significant change after the implementation of CNG. However, the BTX concentration demonstrated a clear relation with the benzene content of gasoline. In addition to the impact of the introduction of CNG the daily variation in PAHs levels was also studied and the PAHs concentrations were observed to be relatively high between 10 pm to 6 am, which gives a proof of a relation with the limited day entry and movement of heavy vehicles in Delhi.

  17. A two-dimensional, transient, compressible isothermal and two-phase model for the air-side electrode of PEM fuel cells

    International Nuclear Information System (INIS)

    Khakbaz Baboli, M.; Kermani, M.J.

    2008-01-01

    A two-dimensional, transient, compressible, isothermal and two-phase flow of reactant-product mixture in the air-side electrode of proton exchange membrane fuel cells (PEMFC) are numerically studied in the present paper. The mixture is composed of four species: oxygen, nitrogen, liquid water and water vapor. The governing PDE's are conservation of the water vapor and oxygen species, momentum equation of the mixture (gas+liquid), mass conservation of the liquid phase, and mass conservation of the mixture. In this study, a separate PDE for the mass conservation of the liquid water is solved to calculate the saturation levels. The capillary pressure was used to determine the slip velocity between the phases. A full compressible form of the momentum equation was used, with the ∇.V preserved in the equation. The Maxwell-Stefan equation was used to model the diffusive fluxes of the multi-component gas mixture. The strongly coupled equations are solved based on a recently developed finite volume SIMPLER scheme of S.V. Patankar, Numerical Heat Transfer and Fluid Flow, Hemisphere Publishing Corp., McGraw-Hill Book Company, 1984. The computational domain consists of two regions; an open area (gas delivery channel) linked to a porous gas diffusion layer (GDL). A single (unified) set of the PDE's are used for the whole domain with the corresponding properties of each sub-domain. A polarization curve for the whole spectrum of the dry and wet regions were obtained. The results were compared with the experiments of E.A. Ticianelli, C.R. Derouin, A. Redondo, S. Srinivasan, J. Electrochem. Soc. 135 (1988) 2209, and good agreements were achieved

  18. An experimental and numerical analysis of the influence of the inlet temperature, equivalence ratio and compression ratio on the HCCI auto-ignition process of Primary Reference Fuels in an engine

    OpenAIRE

    Machrafi, Hatim; Cavadias

    2008-01-01

    In order to understand better the auto-ignition process in an HCCI engine, the influence of some important parameters on the auto-ignition is investigated. The inlet temperature, the equivalence ratio and the compression ratio were varied and their influence on the pressure, the heat release and the ignition delays were measured, The inlet temperature was changed from 25 to 70 degrees C and the equivalence ratio from 0.18 to 0.41, while the compression ratio varied from 6 to 13.5. The fuels t...

  19. Development of novel CO{sub 2}-stable oxygen permeable dual phase membranes for CO{sub 2} capture in an oxy-fuel process

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Huixia

    2012-07-19

    The combustion of fossil fuels in power stations with pure oxygen following the oxy-fuel process allows the Sequestration of CO{sub 2}. The pure oxygen needed can be separated from air by oxygen transporting ceramics like single phase perovskites. However, most of the so far developed single phase perovskites have stability problems in a CO{sub 2} containing atmosphere. Dual phase membranes are micro-scale mixtures of an electron conducting phase and an oxygen ion conducting phase and their compositions can be tailored according to practical requirements, which are considered to be promising substitutes for the single phase perovskite materials. In my thesis the issues of phase stability for perovskite-type material with the common composition Ba{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 3-{delta}} (BSCF) as weil as the development of a series of novel CO{sub 2}-stable dual phase membranes were studied. In Chapter 2, the phase stability and permeation behavior of a dead-end BSCF tube membrane in high-purity oxygen at temperatures below 750 C, were elucidated using powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDXS), high-angle annular dark-field (HAADF) and scanning transmission electron microscopy (STEM). lt was found that parts of the cubic perovskite BSCF transformed into a hexagonal perovskite Ba{sub 0.5{+-}x}Sr{sub 0.5{+-}x}CoO{sub 3-{delta}} (x {approx} 0.1) and a trigonal mixed oxide Ba{sub 1-x}Sr{sub x}CO{sub 2-y}Fe{sub y}O{sub 5{+-}{delta}} (x {approx} 0.15, y {approx} 0.25) in high-purity oxygen at 750 C. On the other hand, it was found that the partial degradation of cubic BSCF perovskite at 750 C was more pronounced under the strongly oxidizing conditions on the oxygen supply (feed) side than on the oxygen release (permeate) side of the membrane. The structural instability of BSCF is attributed to an oxidation of cobalt from Co{sup 2+} to Co{sup 3+} and Co{sup 4+}, which exhibits an ionic radius that is too small to be tolerated by

  20. Experimental study of the effects of natural gas injection timing on the combustion performance and emissions of a turbocharged common rail dual-fuel engine

    International Nuclear Information System (INIS)

    Yang, Bo; Wei, Xing; Xi, Chengxun; Liu, Yifu; Zeng, Ke; Lai, Ming-Chia

    2014-01-01

    Highlights: • Natural gas injection timing has obvious effects on combustion of dual-fuel engine. • Combustion performance is improved with optimized natural gas injection timing. • BSHC and BSCO decreased with retarded natural gas injection timing at low load. • BSNO x increased at part load while reduced at high load with delay N.G. injection. • PM is very low and insensitive to the variation of natural gas injection timing. - Abstract: Natural gas combustion with pilot ignition has been considered to be one of the most promising ways to utilize natural gas in existing diesel engine without serious engine modification and it has been widely researched all over the world. In this study, three experiments of different loads (BMEP 0.240 MPa, 0.480 MPa and 0.767 MPa) were performed on a 2.8 L four-cylinder, natural gas manifold injection dual-fuel engine to investigate the effects of natural gas injection timing on engine combustion performance and emissions. The pilot injection parameters (pilot injection timing and pressure) and natural gas injection pressure remain constant at a speed of 1600 rpm in the experiment. The cylinder pressure, HRR, CoV imep , flame development duration, CA50 and brake thermal efficiency were analyzed. The results indicated that under low and part engine loads, the flame development duration and CA50 can be reduced by properly retarding natural gas injection timing, while the CoV imep increased with retarded natural gas injection timing. As a result, the brake thermal efficiency is increased and the combustion stability slightly deteriorates. Meanwhile, under low and part engine loads, PM emissions in the dual-fuel engine is much lower than that in conventional diesel engines, furthermore, at high load, the PM emissions are near zero. CO and HC emissions are reduced with retarded natural gas injection timing under low and part loads, however, NO x emissions are slightly increased. Under high load, the flame development duration

  1. Experimental investigation of timed manifold injection of acetylene in direct injection diesel engine in dual fuel mode

    International Nuclear Information System (INIS)

    Lakshmanan, T.; Nagarajan, G.

    2010-01-01

    The increase in demand and decrease in availability of fossil fuels with more stringent emission norms have led to research in finding an alternative fuel for internal combustion (IC) engines. Among the alternative fuels, gaseous fuels find a great potential. The gaseous fuel taken up for the present study is acetylene, which possesses excellent combustion properties. Preignition is the major problem with this fuel. In the present study, timed manifold injection technique is adopted to induct the fuel into the IC engine. A four-stroke, 4.4 kW diesel engine is selected, with slight modification in intake manifold for holding the gas injector, which is controlled by an electronic control unit (ECU). By using an ECU, an optimized injection timing of 10 o after top dead center and 90 o crank angle duration are arrived. At this condition, experiments were conducted for the various gas flow rates of 110 g/s, 180 g/s and 240 g/s. The performance was nearer to diesel at full load. Oxides of nitrogen, hydrocarbon and carbon monoxide emission decreased due to lean operation with marginal increase in smoke emission. To conclude, a safe operation of acetylene replacement up to 24% was possible with reduction in emission parameters.

  2. Compressed hydrogen fuelled vehicle at ENEA: Status and development

    International Nuclear Information System (INIS)

    Pede, G.; Ciancia, A.

    1993-01-01

    The world's 500 million road vehicles using internal combustion engines account for roughly half of global oil consumption and, in Italy, for about 50% of all nitrogen oxide and 90% of carbon monoxide emissions. In efforts to conserve petroleum reserves and reduce air pollution, research programs are being conducted to develop hydrogen fueled automotive engines. Hydrogen combustion products are carbon dioxide free, and when burned with a large excess of air, this fuel produces water vapour and only small amounts of nitrogen oxides. Hydrogen fueled vehicles can be made to operate in a dual fuel mode so as to allow the use of petrol or diesel fuel in travel over long distances. Currently, because technical and economic difficulties relevant to hydrogen fuel storage limit driving range and payload (there are bulk and weight problems in compressed gas and metal hydride storage systems, and cost problems in cryogenic storage), only limited research programs are being performed, mainly in Germany (by Mercedes Benz) and Japan. Some recent advances, however, relevant to research in gas storage and gaseous mixtures have been made by ENEA (the Italian Agency for New Technology, Energy and the Environment). This paper outlines the progress being made in ENEA's research efforts which include the development of an electronically controlled hydrogen fuel injection system prototype

  3. DNABIT Compress - Genome compression algorithm.

    Science.gov (United States)

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-22

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, "DNABIT Compress" for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that "DNABIT Compress" algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases.

  4. Compression stockings

    Science.gov (United States)

    Call your health insurance or prescription plan: Find out if they pay for compression stockings. Ask if your durable medical equipment benefit pays for compression stockings. Get a prescription from your doctor. Find a medical equipment store where they can ...

  5. Karakterisasi Unjuk Kerja Diesel Engine Generator Set Sistem Dual Fuel Solar-Syngas Hasil Gasifikasi Briket Municipal Solid Waste (MSW Secara Langsung

    Directory of Open Access Journals (Sweden)

    Achmad Rizkal

    2017-01-01

    Full Text Available Sejalan dengan semakin banyaknya kebutuhan energi untuk dapat digunakan sebagai bahan bakar maka perlu adanya pengembangan gas biomassa sebagai bahan bakar alternatif pada motor pembakaran dalam maka akan dilakukan penelitian mengenai aplikasi sistem dual fuel gas hasil gasifikasi biomassa municipal solid waste (msw pada sistem downdraft dengan minyak solar pada motor diesel stasioner. Penelitian ini bertujuan untuk mengetahui seberapa besar solar yang tersibtitusi dengan adanya penambahan syngas yang disalurkan secara langsung. Penelitian ini dilakukan secara eksperimental dengan proses pemasukan aliran syngas yang dihasilkan downdraft municipal solid waste (MSW kedalam saluran udara mesin diesel generator set secara langsung menggunakan sistem mixer. Pengujian dilakukan dengan putaran konstan 2000 rpm dengan pembebanan bervariasi dari 200 watt sampai dengan 2000 watt dengan interval 200 watt. Bahwa produksi syngas dari reaktor gasifikasi ditambahkan sistem bypass untuk mengetahui kesesuaian antara reaktor gasifikasi dan mesin generatorset data ṁ syngas yang dibutuhkan mesin diesel, ṁ syngas yang di bypass untuk mendapatkan kesesuaian antara produksi syngas dan yang di bypass.  Data-data yang diukur dari penelitian ini menunjukkan bahwa besar nilai mass flowrate gas syngas yang dibutuhkan mesin diesel pada AFR reaktor gasifier 1,39 sebesar 0,0003748 kg/s. Mass flowrate gas syngas yang di bypass menunjukkan nilai 0 pada saat sistem dijalankan karena seluruh gas syngas masuk kedalam ruang bakar. AFR rata-rata sebesar 14,54 ,Nilai Spesifik fuel consumption (sfc mengalami peningkatan 68% dari kondisi standar single fuel , Nilai efesiensi thermal mengalami kenaikan sebesar 7% dari kondisi single fuel, Nilai daya rata-rata sebesar 2,28kW, Nilai torsi rata-rata sebesar 10,94 N.m. Solar yang tersibtitusi sebesar 48%. Nilai temperatur (coolant, mesin, oil, dan gas buang pada setiap pembebanan mengalami kenaikan.

  6. Possible use of dual purpose dry storage casks for transportation and future storage of spent nuclear fuel from IRT-Sofia

    International Nuclear Information System (INIS)

    Manev, L.; Baltiyski, M.

    2003-01-01

    Objectives: The main objective of the present paper is related to one of the priority goals stipulated in Bulgarian Governmental Decision No.332 from May 17, 1999 - removal of SNF from IRT-Sofia site and its exporting for reprocessing and/or for temporary storage at Kozloduy NPP site. The variant of using dual purpose dry storage casks for transportation and future temporary storage of SNF from IRT-Sofia aims to find out a reasonable alternative of the existing till now variant for temporary SNF storage under water in the existing Kozloduy NPP Spent Fuel Storage Facility until its export for reprocessing. Results: Based on the given data for the condition of 73 Spent Nuclear Fuel Assemblies (SNFA) stored in the storage pool and technical data as well as data for available equipment and IRT-Sofia layout the following framework are specified: draft technical features of dual purpose dry storage casks and their overall dimensions; the suitability of the available equipment for safety and reliable performance of transportation and handling operations of assemblies from storage pool to dual purpose dry storage casks; the necessity of new equipment for performance of the above mentioned operations; Assemblies' transportation and handling operations are described; requirements to and conditions for future safety and reliable storage of SNFA loaded casks are determined. When selecting the technical solutions for safety assurance during performance of site handling operations of IRT-Sofia and for description of the exemplary casks the Effective Bulgarian Regulations are considered. The experience of other countries in performance of transfer and transportation of SNFA from such types of research reactors is taken into account. Also, Kozloduy NPP experience in SNF handling operations is taken into account. Conclusions: The Decision of Council of Minister for refurbishment of research reactor into a low power one and its future utilization for experimental and training

  7. Microstructure-property relationships in a gas diffusion layer (GDL) for Polymer Electrolyte Fuel Cells, Part I: effect of compression and anisotropy of dry GDL

    International Nuclear Information System (INIS)

    Holzer, L.; Pecho, O.; Schumacher, J.; Marmet, Ph.; Stenzel, O.; Büchi, F.N.; Lamibrac, A.; Münch, B.

    2017-01-01

    Highlights: • Methods are developed to predict transport properties of dry GDL in PE Fuel Cells. • Diffusivity and Permeability are reliably predicted based on 3D characteristics. • Predictions based on 3D microstructure match well with numerical simulations. • Anisotropy is due to in- and through-plane variation of tortuosity and hydraulic rad. • The methods can be used to predict relative permeability and diffusivity in wet GDL. - Abstract: New quantitative relationships are established between effective properties (gas diffusivity, permeability and electrical conductivity) for a dry GDL (25 BA) from SGL Carbon with the corresponding microstructure characteristics from 3D analysis. These microstructure characteristics include phase volume fractions, geodesic tortuosity, constrictivity and hydraulic radius. The latter two parameters include information from two different size distribution curves for bulges (continuous PSD) and for bottlenecks (MIP-PSD). X-ray tomographic microscopy is performed for GDL at different compression levels and the micro-macro-relationships are then established for the in-plane and through-plane directions. The predicted properties based on these relationships are compared with numerical transport simulations, which give very similar results and which can be summarized as follows: Gas diffusivity is higher in the in-plane than in the through-plane direction. Its variation with compression is mainly related to changes of porosity and geodesic tortuosity. Permeability is dominated by variations in hydraulic radius. Through-plane permeability is slightly higher than in-plane. Anisotropy of electrical conductivity is controlled by tortuosity, which is higher for the through-plane direction. A table with new quantitative relationships is provided, which are considered to be more accurate and precise than older descriptions (e.g. Carman-Kozeny, Bruggeman), because they are based on detailed topological information from 3D analysis

  8. Transient Response and Steady-State Analysis of the Anode of Direct Methanol Fuel Cells Based on Dual-Site Kinetics

    Directory of Open Access Journals (Sweden)

    Lei Xing

    2011-01-01

    Full Text Available An intrinsic time-dependent one-dimensional (1D model and a macro two-dimensional (2D model for the anode of the direct methanol fuel cell (DMFC are presented. The two models are based on the dual-site mechanism, which includes the coverage of intermediate species of methanol, OH, and CO (θM, θOH,Ru, and θCO,Pt on the surface of Pt and Ru. The intrinsic 1D model focused on the analysis of the effects of operating temperature, methanol concentration, and overpotential on the transient response. The macro 2D model emphasises the dimensionless distributions of methanol concentration, overpotential and current density in the catalyst layer which were affected by physical parameters such as thickness, specific area, and operating conditions such as temperature, bulk methanol concentration, and overpotential. The models were developed and solved in the PDEs module of COMSOL Multiphysics, giving good agreement with experimental data. The dimensionless distributions of methanol concentration, overpotential, and current density and the efficiency factor were calculated quantitatively. The models can be used to give accurate simulations for the polarisations of methanol fuel cell.

  9. Numerical investigation of exhaust gas emissions for a dual fuel engine configuration using diesel and pongamia oil.

    Science.gov (United States)

    Mohamed Ibrahim, N H; Udayakumar, M

    2016-12-01

    The investigation presented in this paper focuses on determination of gaseous exhaust emissions by computational simulation during combustion in compression ignition engine with pongamia oil substitution. Combustion is modeled using Equilibrium Constants Method (ECM) with MATLAB program to calculate the mole fraction of 10 combustion products when pongamia oil is burnt along with diesel at variable equivalence ratio and blend ratio. It had been observed that pongamia oil substitution causes decrease in the CO emission and increase in the NO x emission as the blend ratio as well as equivalence ratio increases. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Operating a locomotive on liquid methane fuel

    International Nuclear Information System (INIS)

    Stolz, J.L.

    1992-01-01

    This paper reports that several years ago, Burlington Northern Railroad looked into the feasibility of operating a diesel railroad locomotive to also run on compressed natural gas in a dual-fuel mode. Recognizing the large volume of on-board storage required and other limitations of CNG in the application, a program was begun to fuel a locomotive with liquefied natural gas. Because natural gas composition can vary with source and processing, it was considered desirable to use essentially pure liquid methane as the engine fuel. Initial testing results show the locomotive system achieved full diesel-rated power when operating on liquid methane and with equivalent fuel efficiency. Extended testing, including an American Association of Railroad 500-hour durability test, was undertaken to obtain information on engine life, wear rate and lubrication oil life

  11. Chemical interaction of dual-fuel mixtures in low-temperature oxidation, comparing n -pentane/dimethyl ether and n -pentane/ethanol

    KAUST Repository

    Jin, Hanfeng

    2018-03-22

    With the aim to study potential cooperative effects in the low-temperature oxidation of dual-fuel combinations, we have investigated prototypical hydrocarbon (CH) / oxygenated (CHO) fuel mixtures by doping n-pentane with either dimethyl ether (DME) or ethanol (EtOH). Species measurements were performed in a flow reactor at an equivalence ratio of ϕ = 0.7, at a pressure of p = 970 mbar, and in the temperature range of 450–930 K using electron ionization molecular-beam mass spectrometry (EI-MBMS). Series of different blending ratios were studied including the three pure fuels and mixtures of n-pentane containing 25% and 50% of CHO. Mole fractions and signals of a significant number of species with elemental composition CHO (n = 1–5, x = 0–(n + 2), y = 0–3) were analyzed to characterize the behavior of the mixtures in comparison to that of the individual components. Not unexpectedly, the overall reactivity of n-pentane is decreased when doping with ethanol, while it is promoted by the addition of DME. Interestingly, the present experiments reveal synergistic interactions between n-pentane and DME, showing a stronger effect on the negative temperature coefficient (NTC) for the mixture than for each of the individual components. Reasons for this behavior were investigated and show several oxygenated intermediates to be involved in enhanced OH radical production. Conversely, ethanol is activated by the addition of n-pentane, again involving key OH radical reactions. Although the main focus here is on the experimental results, we have attempted, in a first approximation, to complement the experimental observations by simulations with recent kinetic models. Interesting differences were observed in this comparison for both, fuel consumption and intermediate species production. The inhibition effect of ethanol is not predicted fully, and the synergistic effect of DME is not captured satisfactorily. The exploratory analysis of the experimental results with current

  12. Effects of injection timing on the engine performance and exhaust emissions of a dual-fuel diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Sayin, Cenk [Department of Mechanical Education, Marmara University, 34722 Istanbul (Turkey); Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Izmit (Turkey)

    2009-01-15

    In this study, influence of injection timing on the engine performance and exhaust emissions of a naturally aspirated, single cylinder diesel engine has been experimentally investigated when using ethanol blended diesel fuel from 0% to 15% with an increment of 5%. The engine load was selected as 15 and 30 Nm. The tests were conducted at five different injection timings (21 , 24 , 27 , 30 and 33 CA BTDC) by changing the thickness of advance shim. The experimental test results showed that BSFC and emissions of NO{sub x} and CO{sub 2} increased as BTE and emissions of CO and HC decreased with increasing amount of ethanol in the fuel mixture. When compared to the results of original injection timing (27 CA BTDC), NO{sub x} and CO{sub 2} emissions increased, and unburned HC and CO emissions decreased for the retarded injection timings (21 and 24 CA BTDC) at the all test conditions. On the other side, with the advanced injection timings (30 and 33 CA BTDC), decreasing HC and CO emissions diminished, and NO{sub x} and CO{sub 2} emissions boosted. In terms of BSFC and BTE, retarded and advanced injection timings compared to the original injection timing in the all fuel blends gave negative results for all engine speeds and loads. (author)

  13. Effects of injection timing on the engine performance and exhaust emissions of a dual-fuel diesel engine

    International Nuclear Information System (INIS)

    Sayin, Cenk; Canakci, Mustafa

    2009-01-01

    In this study, influence of injection timing on the engine performance and exhaust emissions of a naturally aspirated, single cylinder diesel engine has been experimentally investigated when using ethanol blended diesel fuel from 0% to 15% with an increment of 5%. The engine load was selected as 15 and 30 Nm. The tests were conducted at five different injection timings (21 deg., 24 deg., 27 deg., 30 deg. and 33 deg. CA BTDC) by changing the thickness of advance shim. The experimental test results showed that BSFC and emissions of NO x and CO 2 increased as BTE and emissions of CO and HC decreased with increasing amount of ethanol in the fuel mixture. When compared to the results of original injection timing (27 deg. CA BTDC), NO x and CO 2 emissions increased, and unburned HC and CO emissions decreased for the retarded injection timings (21 deg. and 24 deg. CA BTDC) at the all test conditions. On the other side, with the advanced injection timings (30 deg. and 33 deg. CA BTDC), decreasing HC and CO emissions diminished, and NO x and CO 2 emissions boosted. In terms of BSFC and BTE, retarded and advanced injection timings compared to the original injection timing in the all fuel blends gave negative results for all engine speeds and loads

  14. Dual-fuel production from restaurant grease trap waste: bio-fuel oil extraction and anaerobic methane production from the post-extracted residue.

    Science.gov (United States)

    Kobayashi, Takuro; Kuramochi, Hidetoshi; Maeda, Kouji; Tsuji, Tomoya; Xu, Kaiqin

    2014-10-01

    An effective way for restaurant grease trap waste (GTW) treatment to generate fuel oil and methane by the combination of physiological and biological processes was investigated. The heat-driven extraction could provide a high purity oil equivalent to an A-grade fuel oil of Japanese industrial standard with 81-93 wt% of extraction efficiency. A post-extracted residue was treated as an anaerobic digestion feedstock, and however, an inhibitory effect of long chain fatty acid (LCFA) was still a barrier for high-rate digestion. From the semi-continuous experiment fed with the residual sludge as a single substrate, it can be concluded that the continuous addition of calcium into the reactor contributed to reducing LCFA inhibition, resulting in the long-term stable operation over one year. Furthermore, the anaerobic reactor performed well with 70-80% of COD reduction and methane productivity under an organic loading rate up to 5.3g-COD/L/d. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Effect of hydrogen-diesel combustion on the performance and combustion parameters of a dual fuelled diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Bose, P.K.; Banerjee, Rahul; Deb, Madhujit [Mechanical Engineering Department, National Institute of Technology, Agartala, Tripura-799055 (India)

    2013-07-01

    Petroleum crude is expected to remain main source of transport fuels at least for the next 20 to 30 years. The petroleum crude reserves however, are declining and consumption of transport fuels particularly in the developing countries is increasing at high rates. Severe shortage of liquid fuels derived from petroleum may be faced in the second half of this century. In this paper, experiments are performed in a fur stroke, single cylinder, compression ignition diesel engine with dual fuel mode. Diesel and hydrogen are used as pilot liquid and primary gaseous fuel, respectively. The objective of this study is to find out the effects on combustion and performance parameters observed at diesel hydrogen fuel mixture for all the different loadings (2kg,4kg,6kg,8kg,10kg and 12kg) in the engine.

  16. Combustion Mode Design with High Efficiency and Low Emissions Controlled by Mixtures Stratification and Fuel Reactivity

    Directory of Open Access Journals (Sweden)

    Hu eWang

    2015-08-01

    Full Text Available This paper presents a review on the combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixture stratification that have been conducted in the authors’ group, including the charge reactivity controlled homogeneous charge compression ignition (HCCI combustion, stratification controlled premixed charge compression ignition (PCCI combustion, and dual-fuel combustion concepts controlled by both fuel reactivity and mixture stratification. The review starts with the charge reactivity controlled HCCI combustion, and the works on HCCI fuelled with both high cetane number fuels, such as DME and n-heptane, and high octane number fuels, such as methanol, natural gas, gasoline and mixtures of gasoline/alcohols, are reviewed and discussed. Since single fuel cannot meet the reactivity requirements under different loads to control the combustion process, the studies related to concentration stratification and dual-fuel charge reactivity controlled HCCI combustion are then presented, which have been shown to have the potential to achieve effective combustion control. The efforts of using both mixture and thermal stratifications to achieve the auto-ignition and combustion control are also discussed. Thereafter, both charge reactivity and mixture stratification are then applied to control the combustion process. The potential and capability of thermal-atmosphere controlled compound combustion mode and dual-fuel reactivity controlled compression ignition (RCCI/highly premixed charge combustion (HPCC mode to achieve clean and high efficiency combustion are then presented and discussed. Based on these results and discussions, combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixtures stratification in the whole operating range is proposed.

  17. Electricity Generation with the Novel 3D Electrode from Swim Wastewater in a Dual-chamber Microbial Fuel Cell

    Directory of Open Access Journals (Sweden)

    Lai Mei-Feng

    2016-01-01

    Full Text Available The swine wastewater has the characteristics of high concentration of organic matter, suspended solids and more high ammonia nitrogen, odor, complex pollution ingredient and large emissions. Microbial fuel cells (MFC is an electrochemical and biological systems related to chemical energy into electrical energy. A two-chambered cubic microbial fuel cell was used to evaluate the effect of a novel 3D electrode which made of iron and copper on the electricity generation. The swine wastewater containing total chemical oxygen demand (TCOD 3300±300 mg/L was used as the feedstock in anode chamber, and the potassium ferricyanide was used as electron acceptor in cathode chamber. The MFC reactor was incubated with the initial pH 7.0 in a air-shaker with a temperature (ca. 35°C and 100 rpm in fed-batch mode. A fixed external resistance (R of 100 Ω was connected between the electrodes and the closed circuit potentials of the MFCs were recorded every 2 min. The results show that using iron 3D electrode has the peak electricity generation of 176 mV at the first two day and maintained the stable electricity voltage of 110 mV during the 5th to 15th days. The COD removal efficiency could reach 80%. Using copper 3D electrode only can generate the peak electricity of 33.1 mV and stable electricity of 27 mV with the COD removal efficiency of 70%.

  18. Dual control of low concentration CO poisoning by anode air bleeding of low temperature polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Klages, Merle; Tjønnås, Johannes; Zenith, Federico; Halvorsen, Ivar J.; Scholta, Joachim

    2016-12-01

    Fuel impurities, fed to a polymer electrolyte membrane fuel cell, can affect stack performance by poisoning of catalyst layers. This paper describes the dynamic behaviour of a stack, including state-of-the-art membrane electrode assemblies (MEA) of three different manufacturers, at different operating conditions. The voltage transients of the step responses to CO poisoning as well as air bleed recovery are compared, revealing differences in performance loss: slow poisoning versus fast recovery, incomplete recovery and voltage oscillation. The recorded behaviour is used to develop a model, based on Tafel equation and first order dynamic response, which can be calibrated to each MEA type. Using this model to predict voltage response, a controller is built with the aim of reducing the total amount of air bleed and monitoring upstream stack processes without the need of sensors measuring the poisoning level. Two controllers are implemented in order to show the concept from a heuristic, easy to implement, and a more technical side allowing more detailed analysis of the synthesis. The heuristic algorithm, based on periodic perturbations of the manipulated variable (air-bleed), is validated on a real stack, revealing a stabilized performance without the need of detailed stack properties knowledge.

  19. Influence of Compression Ratio on High Load Performance and Knock Behavior for Gasoline Port-Fuel Injection, Natural Gas Direct Injection and Blended Operation in a Spark Ignition Engine

    Energy Technology Data Exchange (ETDEWEB)

    Pamminger, Michael; Sevik, James; Scarcelli, Riccardo; Wallner, Thomas; Hall, Carrie

    2017-03-28

    Natural Gas (NG) is an alternative fuel which has attracted a lot of attention recently, in particular in the US due to shale gas availability. The higher hydrogen-to-carbon (H/C) ratio, compared to gasoline, allows for decreasing carbon dioxide emissions throughout the entire engine map. Furthermore, the high knock resistance of NG allows increasing the efficiency at high engine loads compared to fuels with lower knock resistance. NG direct injection (DI) allows for fuel to be added after intake valve closing (IVC) resulting in an increase in power density compared to an injection before IVC. Steady-state engine tests were performed on a single-cylinder research engine equipped with gasoline (E10) port-fuel injection (PFI) and NG DI to allow for in-cylinder blending of both fuels. Knock investigations were performed at two discrete compression ratios (CR), 10.5 and 12.5. Operating conditions span mid-load, wide-open-throttle and boosted conditions, depending on the knock response of the fuel blend. Blended operation was performed using E10 gasoline and NG. An additional gasoline type fuel (E85) with higher knock resistance than E10 was used as a high-octane reference fuel, since the octane rating of E10-NG fuel blends is unknown. Spark timing was varied at different loads under stoichiometric conditions in order to study the knock response as well as the effects on performance and efficiency. As anticipated, results suggest that the knock resistance can be increased significantly by increasing the NG amount. Comparing the engine operation with the least knock resistant fuel, E10 PFI, and the fuel blend with the highest knock resistance, 75% NG DI, shows an increase in indicated mean effective pressure of about 9 bar at CR 12.5. The usage of reference fuels with known knock characteristics allowed an assessment of knock characteristic of intermediate E10-NG blend levels. Mathematical correlations were developed allowing characterizing the occurrence of knocking

  20. High performance fuel technology development

    Energy Technology Data Exchange (ETDEWEB)

    Koon, Yang Hyun; Kim, Keon Sik; Park, Jeong Yong; Yang, Yong Sik; In, Wang Kee; Kim, Hyung Kyu [KAERI, Daejeon (Korea, Republic of)

    2012-01-15

    {omicron} Development of High Plasticity and Annular Pellet - Development of strong candidates of ultra high burn-up fuel pellets for a PCI remedy - Development of fabrication technology of annular fuel pellet {omicron} Development of High Performance Cladding Materials - Irradiation test of HANA claddings in Halden research reactor and the evaluation of the in-pile performance - Development of the final candidates for the next generation cladding materials. - Development of the manufacturing technology for the dual-cooled fuel cladding tubes. {omicron} Irradiated Fuel Performance Evaluation Technology Development - Development of performance analysis code system for the dual-cooled fuel - Development of fuel performance-proving technology {omicron} Feasibility Studies on Dual-Cooled Annular Fuel Core - Analysis on the property of a reactor core with dual-cooled fuel - Feasibility evaluation on the dual-cooled fuel core {omicron} Development of Design Technology for Dual-Cooled Fuel Structure - Definition of technical issues and invention of concept for dual-cooled fuel structure - Basic design and development of main structure components for dual- cooled fuel - Basic design of a dual-cooled fuel rod.

  1. Thermal conductivity of a graphite bipolar plate (BPP) and its thermal contact resistance with fuel cell gas diffusion layers: Effect of compression, PTFE, micro porous layer (MPL), BPP out-of-flatness and cyclic load

    Science.gov (United States)

    Sadeghifar, Hamidreza; Djilali, Ned; Bahrami, Majid

    2015-01-01

    This paper reports on measurements of thermal conductivity of a graphite bipolar plate (BPP) as a function of temperature and its thermal contact resistance (TCR) with treated and untreated gas diffusion layers (GDLs). The thermal conductivity of the BPP decreases with temperature and its thermal contact resistance with GDLs, which has been overlooked in the literature, is found to be dominant over a relatively wide range of compression. The effects of PTFE loading, micro porous layer (MPL), compression, and BPP out-of-flatness are also investigated experimentally. It is found that high PTFE loadings, MPL and even small BPP out-of-flatness increase the BPP-GDL thermal contact resistance dramatically. The paper also presents the effect of cyclic load on the total resistance of a GDL-BPP assembly, which sheds light on the behavior of these materials under operating conditions in polymer electrolyte membrane fuel cells.

  2. Seal performance of thermal aged metal gasket of dual purpose metal cask for interim spent fuel storage after external impact load

    International Nuclear Information System (INIS)

    Takeshi Yokoyama; Masami Kato; Satoshi Itooka

    2005-01-01

    As for interim storage for spent nuclear fuels using dual purpose dry metal cask in Japan, we recognize one of the important technical issues that there is a possibility for the cask with degraded metal gasket during storage to apply to transportation. In our study until 2003 focused on degradation of important components for the cask safety performance during storage and application to transportation, for metal gasket, we conducted property tests for degradation and influence of lid movement on seal performance, and furthermore verification tests. From the results, we developed the method to evaluate leak rate from lid with degraded metal gasket at accidents during transportation and in addition, we found as follows: Lid would hardly move and leak rate would not increase seriously during fire event. Leak rate from lid with degraded metal gasket could be evaluated by using results of leak rate trend depending on horizontal displacement of lid by external impact load. So, with regard to influence of lid movement on seal performance, we conducted additional test for extending horizontal displacement in lid moving in 2004. In addition, seal performance was discussed from the results, both previous and latest test. (authors)

  3. Numerical investigation on the effect of reactivity gradient in an RCCI engine fueled with gasoline and diesel

    International Nuclear Information System (INIS)

    Li, J.; Yang, W.M.; An, H.; Zhou, D.Z.; Yu, W.B.; Wang, J.X.; Li, L.

    2015-01-01

    Highlights: • A chemical reaction mechanism is newly developed for dual fuel combustion. • The developed chemical kinetics is coupled with KIVA4 to model the combustion. • The role of reactivity gradient in RCCI combustion is investigated. • The RCCI (dual fuel mode) combustion is compared with blend fuel mode. - Abstract: The reactivity controlled compression ignition (RCCI), which belongs to dual fuel mode (DFM) combustion has been considered as a promising way to achieve high fuel conversion efficiency and low emissions. By this strategy, a fuel reactivity gradient is formed in the combustion chamber which offers the probability of controlling combustion phasing. In this study, the role of fuel reactivity gradient was examined numerically by comparing a DFM (i.e., RCCI) combustion with other hypothetical cases under one specific load condition. Firstly, a chemical reaction mechanism was developed aiming at a modelling study on dual fuel and blend fuel combustion in internal combustion (IC) engines fueled by gasoline/diesel and gasoline/biodiesel. Ignition delays were validated for 100% diesel, 100% gasoline and 100% biodiesel under 102 conditions in total. Subsequently, the validated reaction mechanism which consists of 107 species and 425 reactions was implemented in coupled KIVA4-CHEMKIN code. Three dimensional validations were further conducted under 3 conditions including pure diesel combustion, and gasoline/diesel DFM combustion with both single and double injection strategies in the engine. To investigate the fuel reactivity gradient, the gasoline/diesel DFM combustion with single injection was compared with other three hypothetical cases, one of which was DFM without fuel reactivity gradient, two were the blend fuel mode but with different start of injection (SOI) timings. The results showed that the fuel reactivity gradient could retard the ignition timing, reduce heat release rate, and ease peak pressure rise rate. In addition, low levels of NO

  4. Influence of carbon electrode material on energy recovery from winery wastewater using a dual-chamber microbial fuel cell.

    Science.gov (United States)

    Penteado, Eduardo D; Fernandez-Marchante, Carmen M; Zaiat, Marcelo; Gonzalez, Ernesto R; Rodrigo, Manuel A

    2017-06-01

    The aim of this work was to evaluate three carbon materials as anodes in microbial fuel cells (MFCs), clarifying their influence on the generation of electricity and on the treatability of winery wastewater, a highly organic-loaded waste. The electrode materials tested were carbon felt, carbon cloth and carbon paper and they were used at the same time as anode and cathode in the tests. The MFC equipped with carbon felt reached the highest voltage and power (72 mV and 420 mW m -2 , respectively), while the lowest values were observed when carbon paper was used as electrode (0.2 mV and 8.37·10 -6  mW m -2 , respectively). Chemical oxygen demand (COD) removal from the wastewater was observed to depend on the electrode material, as well. When carbon felt was used, the MFC showed the highest average organic matter consumption rate (650 mg COD L -1  d -1 ), whereas by using carbon paper the rate decreased to 270 mg COD L -1  d -1 . Therefore, both electricity generation and organic matter removal are strongly related not to the chemical composition of the electrode (which was graphite carbon in the three electrodes), but to its surface features and, consequently, to the amount of biomass adhered to the electrode surface.

  5. An experimental and numerical analysis of the influence of the inlet temperature, equivalence ratio and compression ratio on the HCCI auto-ignition process of Primary Reference Fuels in an engine

    Energy Technology Data Exchange (ETDEWEB)

    Machrafi, Hatim [UPMC Universite Paris 06, LGPPTS, Ecole Nationale Superieure de Chimie de Paris, 11, rue de Pierre et Marie Curie, 75005 Paris (France); UPMC Universite Paris 06, Institut Jean Le Rond D' Alembert (France); Cavadiasa, Simeon [UPMC Universite Paris 06, Institut Jean Le Rond D' Alembert (France)

    2008-11-15

    In order to understand better the auto-ignition process in an HCCI engine, the influence of some important parameters on the auto-ignition is investigated. The inlet temperature, the equivalence ratio and the compression ratio were varied and their influence on the pressure, the heat release and the ignition delays were measured. The inlet temperature was changed from 25 to 70 C and the equivalence ratio from 0.18 to 0.41, while the compression ratio varied from 6 to 13.5. The fuels that were investigated were PRF40 and n-heptane. These three parameters appeared to decrease the ignition delays, with the inlet temperature having the least influence and the compression ratio the most. A previously experimentally validated reduced surrogate mechanism, for mixtures of n-heptane, iso-octane and toluene, has been used to explain observations of the auto-ignition process. The same kinetic mechanism is used to better understand the underlying chemical and physical phenomena that make the influence of a certain parameter change according to the operating conditions. This can be useful for the control of the auto-ignition process in an HCCI engine. (author)

  6. Experimental Studies of Diestrol-Micro Emulsion Fuel in a Direct Injection Compression Ignition Engine under Varying Injection Pressures and Timings

    Science.gov (United States)

    Kannan, Gopal Radhakrishnan

    2018-02-01

    The research work on biodiesel becomes more attractive in the context of limited availability of petroleum fuels and rapid increase of harmful emissions from diesel engine using conventional fossil fuels. The present investigation has dealt with the influence of biodiesel-diesel-ethanol (diestrol) water micro emulsion fuel (B60D20E20M) on the performance, emission and combustion characteristics of a diesel engine under different injection pressure and timing. The results revealed that the maximum brake thermal efficiency of 32.4% was observed at an injection pressure of 260 bar and injection timing of 25.5°bTDC. In comparison with diesel, micro emulsion fuel showed reduction in carbon monoxide (CO) and total hydrocarbon (THC) by 40 and 24%, respectively. Further, micro emulsion fuel decreased nitric oxide (NO) emission and smoke emission by 7 and 20.7%, while the carbon dioxide (CO2) emission is similar to that of diesel.

  7. Wellhead compression

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, Joe [Sertco Industries, Inc., Okemah, OK (United States); Vazquez, Daniel [Hoerbiger Service Latin America Inc., Deerfield Beach, FL (United States); Jacobs, Denis Richard [Hoerbiger do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)

    2012-07-01

    Over time, all wells experience a natural decline in oil and gas production. In gas wells, the major problems are liquid loading and low downhole differential pressures which negatively impact total gas production. As a form of artificial lift, wellhead compressors help reduce the tubing pressure resulting in gas velocities above the critical velocity needed to surface water, oil and condensate regaining lost production and increasing recoverable reserves. Best results come from reservoirs with high porosity, high permeability, high initial flow rates, low decline rates and high total cumulative production. In oil wells, excessive annulus gas pressure tends to inhibit both oil and gas production. Wellhead compression packages can provide a cost effective solution to these problems by reducing the system pressure in the tubing or annulus, allowing for an immediate increase in production rates. Wells furthest from the gathering compressor typically benefit the most from wellhead compression due to system pressure drops. Downstream compressors also benefit from higher suction pressures reducing overall compression horsepower requirements. Special care must be taken in selecting the best equipment for these applications. The successful implementation of wellhead compression from an economical standpoint hinges on the testing, installation and operation of the equipment. Key challenges and suggested equipment features designed to combat those challenges and successful case histories throughout Latin America are discussed below.(author)

  8. Dual-Mode Combustor

    Science.gov (United States)

    Trefny, Charles J (Inventor); Dippold, Vance F (Inventor)

    2013-01-01

    A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

  9. The Comparison of Hydrotreated Vegetable Oils With Respect to Petroleum Derived Fuels and the Effects of Transient Plasma Ignition in a Compression-Ignition Engine

    Science.gov (United States)

    2012-09-01

    Content per Combustion J FAME Fatty Acid Methyl Ester FMEP Friction Mean Effective Pressure PSI or Bar FT Fischer-Tropsch h Heat...recently, algae-derived oils. Biodiesel has gained popularity in North America over the past decade, but the ester content of Fatty Acid Methyl ... Ester ( FAME ) fuel creates both cold weather and water- based operational issues. The Fischer-Tropsch (FT) process produces liquid fuels from “syngas,” a

  10. Diseño y optimización del sistema de renovación de la carga de un motor dual fuel para transporte pesado mediante sobrealimentación en doble etapa

    OpenAIRE

    SIRVENT SANJOSÉ, ROBERTO ANDRÉS

    2016-01-01

    El trabajo consiste en el diseño del sistema de admisión y escape de un motor dual-fuel para transporte pesado. Se deberá seleccionar la arquitectura adecuada para poder conseguir las condiciones de deseadas en el interior del cilindro (sistema de sobrealimentación, producción de EGR). Se deberá también seleccionar la estrategia adecuada para el control de cada uno de los elementos utilizados. Sirvent Sanjosé, RA. (2016). Diseño y optimización del sistema de renovación de la carga de un mo...

  11. Speech Compression

    Directory of Open Access Journals (Sweden)

    Jerry D. Gibson

    2016-06-01

    Full Text Available Speech compression is a key technology underlying digital cellular communications, VoIP, voicemail, and voice response systems. We trace the evolution of speech coding based on the linear prediction model, highlight the key milestones in speech coding, and outline the structures of the most important speech coding standards. Current challenges, future research directions, fundamental limits on performance, and the critical open problem of speech coding for emergency first responders are all discussed.

  12. Autoignition characterization of primary reference fuels and n-heptane/n-butanol mixtures in a constant volume combustion device and homogeneous charge compression ignition engine

    KAUST Repository

    Baumgardner, Marc E.; Sarathy, Mani; Má rchese, Anthony J.

    2013-01-01

    -octane, n-heptane, and n-butanol were tested in the FIT - 28 test runs with 25 ignition measurements for each test run, totaling 350 individual tests in all. These experimental results supported previous findings that fuel blends with high alcohol content

  13. Technology Demonstration of Qualified Vehicle Modifier (QVM) Compressed Natural Gas (CNG) and Gasoline Fueled Ford F-150 Series Bifuel Prep Vehicles at Ft. Hood, TX

    National Research Council Canada - National Science Library

    Alvarez, R

    2000-01-01

    ...) of 1988, the Clean Air Act (CAA) Amendments of 1990, and the Energy Policy Act of 1992. The objectives of the program were to demonstrate the acceptability of alternative-fueled- vehicles in a Department of Defense (DOD) U.S...

  14. Metal Hydride Compression

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Terry A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Bowman, Robert [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Smith, Barton [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Anovitz, Lawrence [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jensen, Craig [Hawaii Hydrogen Carriers LLC, Honolulu, HI (United States)

    2017-07-01

    Conventional hydrogen compressors often contribute over half of the cost of hydrogen stations, have poor reliability, and have insufficient flow rates for a mature FCEV market. Fatigue associated with their moving parts including cracking of diaphragms and failure of seal leads to failure in conventional compressors, which is exacerbated by the repeated starts and stops expected at fueling stations. Furthermore, the conventional lubrication of these compressors with oil is generally unacceptable at fueling stations due to potential fuel contamination. Metal hydride (MH) technology offers a very good alternative to both conventional (mechanical) and newly developed (electrochemical, ionic liquid pistons) methods of hydrogen compression. Advantages of MH compression include simplicity in design and operation, absence of moving parts, compactness, safety and reliability, and the possibility to utilize waste industrial heat to power the compressor. Beyond conventional H2 supplies of pipelines or tanker trucks, another attractive scenario is the on-site generating, pressuring and delivering pure H2 at pressure (≥ 875 bar) for refueling vehicles at electrolysis, wind, or solar generating production facilities in distributed locations that are too remote or widely distributed for cost effective bulk transport. MH hydrogen compression utilizes a reversible heat-driven interaction of a hydride-forming metal alloy with hydrogen gas to form the MH phase and is a promising process for hydrogen energy applications [1,2]. To deliver hydrogen continuously, each stage of the compressor must consist of multiple MH beds with synchronized hydrogenation & dehydrogenation cycles. Multistage pressurization allows achievement of greater compression ratios using reduced temperature swings compared to single stage compressors. The objectives of this project are to investigate and demonstrate on a laboratory scale a two-stage MH hydrogen (H2) gas compressor with a

  15. Effectiveness of the neutron-shield nanocomposites for a dual-purpose cask of Bushehr's Water–Water Energetic Reactor (VVER 1000 nuclear-power-plant spent fuels

    Directory of Open Access Journals (Sweden)

    Mahdi Rezaeian

    2017-10-01

    Full Text Available In order to perform dry interim storage and transportation of the spent-fuel assemblies of the Bushehr Nuclear Power Plant, dual-purpose casks can be utilized. The effectiveness of different neutron-shield materials for the dual-purpose cask was analyzed through a set of calculations carried out using the Monte Carlo N-Particle (MCNP code. The dose rate for the dual-purpose cask utilizing the recently developed materials of epoxy/clay/B4C and epoxy/clay/B4C/carbon fiber was less than the allowable radiation level of 2 mSv/h at any point and 0.1 mSv/h at 2 m from the external surface of the cask. By utilization of epoxy/clay/B4C instead of an ethylene glycol/water mixture, the dose rates on the side surface of the cask due to neutron sources and consequent secondary gamma rays will be reduced by 17.5% and 10%, respectively. The overall dose rate in this case will be reduced by 11%.

  16. Fuels and Combustion

    KAUST Repository

    Johansson, Bengt

    2016-08-17

    This chapter discusses the combustion processes and the link to the fuel properties that are suitable for them. It describes the basic three concepts, including spark ignition (SI) and compression ignition (CI), and homogeneous charge compression ignition (HCCI). The fuel used in a CI engine is vastly different from that in an SI engine. In an SI engine, the fuel should sustain high pressure and temperature without autoignition. Apart from the dominating SI and CI engines, it is also possible to operate with a type of combustion: autoignition. With HCCI, the fuel and air are fully premixed before combustion as in the SI engine, but combustion is started by the increased pressure and temperature during the compression stroke. Apart from the three combustion processes, there are also a few combined or intermediate concepts, such as Spark-Assisted Compression Ignition (SACI). Those concepts are discussed in terms of the requirements of fuel properties.

  17. Fuels and Combustion

    KAUST Repository

    Johansson, Bengt

    2016-01-01

    This chapter discusses the combustion processes and the link to the fuel properties that are suitable for them. It describes the basic three concepts, including spark ignition (SI) and compression ignition (CI), and homogeneous charge compression ignition (HCCI). The fuel used in a CI engine is vastly different from that in an SI engine. In an SI engine, the fuel should sustain high pressure and temperature without autoignition. Apart from the dominating SI and CI engines, it is also possible to operate with a type of combustion: autoignition. With HCCI, the fuel and air are fully premixed before combustion as in the SI engine, but combustion is started by the increased pressure and temperature during the compression stroke. Apart from the three combustion processes, there are also a few combined or intermediate concepts, such as Spark-Assisted Compression Ignition (SACI). Those concepts are discussed in terms of the requirements of fuel properties.

  18. 26 CFR 48.4041-21 - Compressed natural gas (CNG).

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Compressed natural gas (CNG). 48.4041-21 Section... natural gas (CNG). (a) Delivery of CNG into the fuel supply tank of a motor vehicle or motorboat—(1) Imposition of tax. Tax is imposed on the delivery of compressed natural gas (CNG) into the fuel supply tank...

  19. A comparative experimental study on engine operating on premixed charge compression ignition and compression ignition mode

    Directory of Open Access Journals (Sweden)

    Bhiogade Girish E.

    2017-01-01

    Full Text Available New combustion concepts have been recently developed with the purpose to tackle the problem of high emissions level of traditional direct injection Diesel engines. A good example is the premixed charge compression ignition combustion. A strategy in which early injection is used causing a burning process in which the fuel burns in the premixed condition. In compression ignition engines, soot (particulate matter and NOx emissions are an extremely unsolved issue. Premixed charge compression ignition is one of the most promising solutions that combine the advantages of both spark ignition and compression ignition combustion modes. It gives thermal efficiency close to the compression ignition engines and resolves the associated issues of high NOx and particulate matter, simultaneously. Premixing of air and fuel preparation is the challenging part to achieve premixed charge compression ignition combustion. In the present experimental study a diesel vaporizer is used to achieve premixed charge compression ignition combustion. A vaporized diesel fuel was mixed with the air to form premixed charge and inducted into the cylinder during the intake stroke. Low diesel volatility remains the main obstacle in preparing premixed air-fuel mixture. Exhaust gas re-circulation can be used to control the rate of heat release. The objective of this study is to reduce exhaust emission levels with maintaining thermal efficiency close to compression ignition engine.

  20. State of the art of NOx mitigation technologies and their effect on the performance and emission characteristics of biodiesel-fueled Compression Ignition engines

    International Nuclear Information System (INIS)

    Palash, S.M.; Masjuki, H.H.; Kalam, M.A.; Masum, B.M.; Sanjid, A.; Abedin, M.J.

    2013-01-01

    Highlights: • Different NO x reduction technologies are discussed along with their implementation. • EGR rate up to 25% is feasible considering engine performance and other emissions. • ITR technology reduces NO x fairly but increases other emissions, it also reduces performance. • LTC reduces NO x and PM emissions simultaneously but increases HC and CO emissions. • Water injection and emulsion reduce NO x (up to 38%) and PM but increases HC and CO emissions. - Abstract: Biodiesel fuels have the potential to become a reliable substitute for diesel which is used moderately to meet the current energy demands. This fuel can be produced from new or used vegetable oils, non-edible sources and animal fats, which are non-toxic, biodegradable and renewable. In spite of the many advantages of using biodiesel, most of the researchers have reported that they produce higher NO x emissions compared to diesel, which is a deterrent to the market expansion of these fuels. In this study, the different paths to reduce NO x emissions from diesel engines by applying several technologies, such as using additives into fuel, exhaust gas recirculation (EGR), water injection (WI), emulsion technology (ET), injection timing retardation (ITR), simultaneous technology (ST) and low temperature combustion (LTC) mode are reviewed briefly. The impacts of different NO x mitigation technologies on biodiesel-fueled diesel engine performance and emissions are also analyzed critically and different methods of their implementation are shown. This paper also provides a comparison of different NO x mitigation technologies based on previous articles related to this topic. From this comparative study, it was found that the average reduction of NO x emissions by using additives, EGR, WI and ET, ITR, ST and LTC are in the ranges 4–45%, 26–84%, 10–38%, 9.77–37%, 22–95% and 66–93% respectively, compared to biodiesel combustion without applying technologies. However, the average reduction

  1. Steam reforming of fuel to hydrogen in fuel cells

    Science.gov (United States)

    Fraioli, Anthony V.; Young, John E.

    1984-01-01

    A fuel cell capable of utilizing a hydrocarbon such as methane as fuel and having an internal dual catalyst system within the anode zone, the dual catalyst system including an anode catalyst supporting and in heat conducting relationship with a reforming catalyst with heat for the reforming reaction being supplied by the reaction at the anode catalyst.

  2. Numerical investigation on the combined effects of varying piston bowl geometries and ramp injection rate-shapes on the combustion characteristics of a kerosene-diesel fueled direct injection compression ignition engine

    International Nuclear Information System (INIS)

    Tay, Kun Lin; Yang, Wenming; Zhao, Feiyang; Yu, Wenbin; Mohan, Balaji

    2017-01-01

    Highlights: • Effect of injection rate-shaping on heat-release is significant with less turbulence. • Two peak heat-releases are seen for the shallow-depth re-entrant piston. • Significant combustion phasing occurs with kerosene usage and high turbulence. - Abstract: In this work, the combustion characteristics of a direct injection compression ignition (DICI) engine fueled with kerosene-diesel blends, using different piston bowl geometries together with varying injection rate-shapes were investigated. A total of three combustion bowl geometries, namely the omega combustion chamber (OCC), the shallow-depth combustion chamber (SCC) and the shallow-depth re-entrant combustion chamber (SRCC), were used together with six different ramp injection rate-shapes and pure diesel, kerosene-diesel and pure kerosene fuels. It is seen that the SRCC geometry, which has the shortest throat length, gives the highest turbulence kinetic energy (TKE) and this resulted in two peak heat-releases, with a primary peak heat-release during the premixed combustion phase and a secondary peak heat-release during the mixing-controlled combustion phase. In addition, the SCC geometry gives rather distinct premixed combustion and mixing-controlled combustion phases due to the fact that combustion is predominantly controlled by the injected fuel spray itself because of less turbulence. Also, when kerosene is used in place of diesel, the heat-release during the premixed combustion phase increases and diminishes during the mixing-controlled and late combustion phases. It is interesting to note that the effect of injection rate-shaping on the heat-release rate is more obvious for bowl geometries that generate less TKE. Moreover, bowl geometries that generate higher TKEs as well as fuels with lower viscosities generally give lower carbon monoxide (CO) emissions and higher nitrogen oxide (NO) emissions. More importantly, it is possible to achieve low NO and CO emissions simultaneously by using the

  3. Dual Regression

    OpenAIRE

    Spady, Richard; Stouli, Sami

    2012-01-01

    We propose dual regression as an alternative to the quantile regression process for the global estimation of conditional distribution functions under minimal assumptions. Dual regression provides all the interpretational power of the quantile regression process while avoiding the need for repairing the intersecting conditional quantile surfaces that quantile regression often produces in practice. Our approach introduces a mathematical programming characterization of conditional distribution f...

  4. Improved Hypersonic Inlet Performance Using Validated Strut Compression Designs

    Science.gov (United States)

    Bulman, M. J.; Stout, P. W.; Fernandez, R.

    1997-01-01

    Aerojet is currently executing two Strutjet propulsion contracts: one a Rocket Based Combined Cycle (RBCC) engine for a NASA-Marshall Space Flight Center (MSFC) Advanced Reusable Transportation Technology (ARTT) program, the second a Dual Mode Ram/Scramjet engine for a USAF Wright Laboratories Storable Fuel Scramjet Flow Path Concepts program. The engines employed in both programs operate at supersonic and low hypersonic speeds and use inlets employing forebody external and sidewall compression. Aerojet has developed and validated a successful design methodology applicable to these inlet types. Design features include an integrated vehicle forebody, external side compression struts, strut sidewall and throat bleed, a throat shock trap, and variable geometry internal contraction. Computation Fluid Dynamic (CFD) predictions and test data show these inlets allow substantially increased flow turning angles over other designs. These increased flow turning angles allow shorter and lighter engines than current designs, which in turn enables higher performing vehicles with broad operating characteristics. This paper describes the designs of two different inlets evaluated by the NASA-MSFC and USAF programs, discusses the results of wind tunnel tests performed by NASA-Lewis Research Center, and provides correlations of test data with CFD predictions. Parameters of interest include low Mach number starting capability, start sensitivity as a function of back pressure at various contraction ratios, flow turning angles, strut and throat bleed effects, and pressure recovery at various Mach numbers.

  5. Compressed air energy storage system

    Science.gov (United States)

    Ahrens, Frederick W.; Kartsounes, George T.

    1981-01-01

    An internal combustion reciprocating engine is operable as a compressor during slack demand periods utilizing excess power from a power grid to charge air into an air storage reservoir and as an expander during peak demand periods to feed power into the power grid utilizing air obtained from the air storage reservoir together with combustible fuel. Preferably the internal combustion reciprocating engine is operated at high pressure and a low pressure turbine and compressor are also employed for air compression and power generation.

  6. Modeling of hybrid vehicle fuel economy and fuel engine efficiency

    Science.gov (United States)

    Wu, Wei

    "Near-CV" (i.e., near-conventional vehicle) hybrid vehicles, with an internal combustion engine, and a supplementary storage with low-weight, low-energy but high-power capacity, are analyzed. This design avoids the shortcoming of the "near-EV" and the "dual-mode" hybrid vehicles that need a large energy storage system (in terms of energy capacity and weight). The small storage is used to optimize engine energy management and can provide power when needed. The energy advantage of the "near-CV" design is to reduce reliance on the engine at low power, to enable regenerative braking, and to provide good performance with a small engine. The fuel consumption of internal combustion engines, which might be applied to hybrid vehicles, is analyzed by building simple analytical models that reflect the engines' energy loss characteristics. Both diesel and gasoline engines are modeled. The simple analytical models describe engine fuel consumption at any speed and load point by describing the engine's indicated efficiency and friction. The engine's indicated efficiency and heat loss are described in terms of several easy-to-obtain engine parameters, e.g., compression ratio, displacement, bore and stroke. Engine friction is described in terms of parameters obtained by fitting available fuel measurements on several diesel and spark-ignition engines. The engine models developed are shown to conform closely to experimental fuel consumption and motored friction data. A model of the energy use of "near-CV" hybrid vehicles with different storage mechanism is created, based on simple algebraic description of the components. With powertrain downsizing and hybridization, a "near-CV" hybrid vehicle can obtain a factor of approximately two in overall fuel efficiency (mpg) improvement, without considering reductions in the vehicle load.

  7. Chemical interaction of dual-fuel mixtures in low-temperature oxidation, comparing n -pentane/dimethyl ether and n -pentane/ethanol

    KAUST Repository

    Jin, Hanfeng; Pieper, Julia; Hemken, Christian; Brä uer, Eike; Ruwe, Lena; Kohse-Hö inghaus, Katharina

    2018-01-01

    , we have attempted, in a first approximation, to complement the experimental observations by simulations with recent kinetic models. Interesting differences were observed in this comparison for both, fuel consumption and intermediate species production

  8. DNABIT Compress – Genome compression algorithm

    OpenAIRE

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-01

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, “DNABIT Compress” for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our ...

  9. Free compression tube. Applications

    Science.gov (United States)

    Rusu, Ioan

    2012-11-01

    During the flight of vehicles, their propulsion energy must overcome gravity, to ensure the displacement of air masses on vehicle trajectory, to cover both energy losses from the friction between a solid surface and the air and also the kinetic energy of reflected air masses due to the impact with the flying vehicle. The flight optimization by increasing speed and reducing fuel consumption has directed research in the aerodynamics field. The flying vehicles shapes obtained through studies in the wind tunnel provide the optimization of the impact with the air masses and the airflow along the vehicle. By energy balance studies for vehicles in flight, the author Ioan Rusu directed his research in reducing the energy lost at vehicle impact with air masses. In this respect as compared to classical solutions for building flight vehicles aerodynamic surfaces which reduce the impact and friction with air masses, Ioan Rusu has invented a device which he named free compression tube for rockets, registered with the State Office for Inventions and Trademarks of Romania, OSIM, deposit f 2011 0352. Mounted in front of flight vehicles it eliminates significantly the impact and friction of air masses with the vehicle solid. The air masses come into contact with the air inside the free compression tube and the air-solid friction is eliminated and replaced by air to air friction.

  10. DNABIT Compress – Genome compression algorithm

    Science.gov (United States)

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-01

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, “DNABIT Compress” for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that “DNABIT Compress” algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases. PMID:21383923

  11. Thermofluidic compression effects to achieve combustion in a low-compression scramjet engine

    Science.gov (United States)

    Moura, A. F.; Wheatley, V.; Jahn, I.

    2017-12-01

    The compression provided by a scramjet inlet is an important parameter in its design. It must be low enough to limit thermal and structural loads and stagnation pressure losses, but high enough to provide the conditions favourable for combustion. Inlets are typically designed to achieve sufficient compression without accounting for the fluidic, and subsequently thermal, compression provided by the fuel injection, which can enable robust combustion in a low-compression engine. This is investigated using Reynolds-averaged Navier-Stokes numerical simulations of a simplified scramjet engine designed to have insufficient compression to auto-ignite fuel in the absence of thermofluidic compression. The engine was designed with a wide rectangular combustor and a single centrally located injector, in order to reduce three-dimensional effects of the walls on the fuel plume. By varying the injected mass flow rate of hydrogen fuel (equivalence ratios of 0.22, 0.17, and 0.13), it is demonstrated that higher equivalence ratios lead to earlier ignition and more rapid combustion, even though mean conditions in the combustor change by no more than 5% for pressure and 3% for temperature with higher equivalence ratio. By supplementing the lower equivalence ratio with helium to achieve a higher mass flow rate, it is confirmed that these benefits are primarily due to the local compression provided by the extra injected mass. Investigation of the conditions around the fuel plume indicated two connected mechanisms. The higher mass flow rate for higher equivalence ratios generated a stronger injector bow shock that compresses the free-stream gas, increasing OH radical production and promoting ignition. This was observed both in the higher equivalence ratio case and in the case with helium. This earlier ignition led to increased temperature and pressure downstream and, consequently, stronger combustion. The heat release from combustion provided thermal compression in the combustor, further

  12. Dual Spark Plugs For Stratified-Charge Rotary Engine

    Science.gov (United States)

    Abraham, John; Bracco, Frediano V.

    1996-01-01

    Fuel efficiency of stratified-charge, rotary, internal-combustion engine increased by improved design featuring dual spark plugs. Second spark plug ignites fuel on upstream side of main fuel injector; enabling faster burning and more nearly complete utilization of fuel.

  13. Processing of dual-orthogonal cw polarimetric radar signals

    NARCIS (Netherlands)

    Babur, G.

    2009-01-01

    The thesis consists of two parts. The first part is devoted to the theory of dual-orthogonal polarimetric radar signals with continuous waveforms. The thesis presents a comparison of the signal compression techniques, namely correlation and de-ramping methods, for the dual-orthogonal sophisticated

  14. The Explicit Determinations Of Dual Plane Curves And Dual Helices In Terms Of Its Dual Curvature And Dual Torsion

    OpenAIRE

    Lee Jae Won; Choi Jin Ho; Jin Dae Ho

    2014-01-01

    In this paper, we give the explicit determinations of dual plane curves, general dual helices and dual slant helices in terms of its dual curvature and dual torsion as a fundamental theory of dual curves in a dual 3-space

  15. Evaluación energética de un sistema de generación de 400 kWe en modo diesel‐gas licuado de petróleo//Energy analysis of a 400 kWe power system operated on dual fuel mode with diesel‐liquefied petroleum gas

    Directory of Open Access Journals (Sweden)

    Carlos‐A. Forero-Núñez

    2014-08-01

    Full Text Available El constante aumento en los precios de los combustibles impulsó el desarrollo de sistemas energéticos cada vez más eficientes y flexibles, los cuales permitan el uso de distintos tipos de combustibles, tales como el gas licuado de petróleo (GLP. El presente trabajo buscó analizar el comportamiento energético y ambiental que tiene una planta de generación de 400 kWe operada en modo diesel y dual diesel-GLP de pozo. La eficiencia energética total del sistema en el punto de máxima carga fue igual a 39,9 % en modo diesel y 35,1 % con una relación de sustitución del 28,5 % en modo dual. La adición de GLP resultó en una disminución del índice de emisiones de CO2 de 0,76 a 0,71 kgkWh-1. El adecuado comportamiento del sistema genera interesantes oportunidades para la disminución del impacto ambiental causado por los sistemas diesel, la diversificación de la canasta energética y la reducción de costos de generación eléctrica en pozos petroleros.Palabras claves: eficiencia energética, diesel, GLP, modo dual.________________________________________________________________________________AbstractThe continuous increase of the fuel costs promoted the development of more efficient and flexible power systems, which could use alternative fuels such as liquefied petroleum gas (LPG. This work aimed to analyze the performance and environmental effect of a 400kWe power system fed with diesel and diesel-LGP on a dual fuel mode. The total electric efficiency of this system at his maximum load was 39,9 % with diesel and 35,1 % at a 28,5 % substitution level on a dual fuel mode. The addition of LPG decreased the CO2 emission index from 0,76 to 0,71 kgkWh-1. The proper behavior of this system on a dual fuel mode mitigated the environmental impact of diesel internal combustion engines, diversified the energy market, and reduced the power generation costs onto petroleum extraction wells.Key words: energy efficiency, diesel, LPG, dual fuel mode.

  16. 40 CFR 600.206-93 - Calculation and use of fuel economy values for gasoline-fueled, diesel-fueled, electric, alcohol...

    Science.gov (United States)

    2010-07-01

    ... EMISSIONS OF MOTOR VEHICLES Fuel Economy Regulations for 1977 and Later Model Year Automobiles-Procedures... equivalent petroleum-based fuel economy value exists for an electric vehicle configuration, all values for... values for gasoline-fueled, diesel-fueled, electric, alcohol-fueled, natural gas-fueled, alcohol dual...

  17. Envera Variable Compression Ratio Engine

    Energy Technology Data Exchange (ETDEWEB)

    Charles Mendler

    2011-03-15

    Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low

  18. Nuclear fuel rod loading apparatus

    International Nuclear Information System (INIS)

    King, H.B.

    1981-01-01

    A nuclear fuel loading apparatus, incorporating a microprocessor control unit, is described which automatically loads nuclear fuel pellets into dual fuel rods with a minimum of manual involvement and in a manner and sequence to ensure quality control and accuracy. (U.K.)

  19. QCD Dual

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2009-01-01

    We uncover a novel solution of the 't Hooft anomaly matching conditions for QCD. Interestingly in the perturbative regime the new gauge theory, if interpreted as a possible QCD dual, predicts the critical number of flavors above which QCD in the nonperturbative regime, develops an infrared stable...

  20. Loads imposed on dual purpose casks in German on-site-storage facilities for long term intermediate storage of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, N.; Rabe, O. [TUeV NORD EnSys Hannover GmbH und Co. KG, Hanover (Germany)

    2004-07-01

    In accordance with recent changes of the atomic energy act and in order to secure reliable removal of spent fuel from the nuclear power plants' fuel storage ponds the German utilities filed license applications for a total of 12 onsite- storage facilities for spent fuel assemblies. By the end of 2003 the last of these storage facilities were licensed and are currently under construction. The first on-site-storage facility of that line became operational in late 2002. There are several design lines of storage facilities with different handling procedures or possible accident conditions. Short term interim storage facilities for a few casks are characterized by individual concrete hoods shielding the casks in horizontal position whereas long term intermediate storage facilities currently erected for large numbers of casks typically feature a condensed pattern of casks stored in upright position and massive structures of reinforced concrete. TUeV Hannover/Sachsen-Anhalt e. V. (now TUeV NORD EnSys Hannover GmbH and Co. KG) has been contracted as a body of independent experts for the assessment of all related safety requirements on behalf of the national licensing authority, the federal office for radiation protection (BfS).

  1. Loads imposed on dual purpose casks in German on-site-storage facilities for long term intermediate storage of spent nuclear fuel

    International Nuclear Information System (INIS)

    Wetzel, N.; Rabe, O.

    2004-01-01

    In accordance with recent changes of the atomic energy act and in order to secure reliable removal of spent fuel from the nuclear power plants' fuel storage ponds the German utilities filed license applications for a total of 12 onsite- storage facilities for spent fuel assemblies. By the end of 2003 the last of these storage facilities were licensed and are currently under construction. The first on-site-storage facility of that line became operational in late 2002. There are several design lines of storage facilities with different handling procedures or possible accident conditions. Short term interim storage facilities for a few casks are characterized by individual concrete hoods shielding the casks in horizontal position whereas long term intermediate storage facilities currently erected for large numbers of casks typically feature a condensed pattern of casks stored in upright position and massive structures of reinforced concrete. TUeV Hannover/Sachsen-Anhalt e. V. (now TUeV NORD EnSys Hannover GmbH and Co. KG) has been contracted as a body of independent experts for the assessment of all related safety requirements on behalf of the national licensing authority, the federal office for radiation protection (BfS)

  2. High performance polymer electrolyte fuel cells with ultra-low Pt loading electrodes prepared by dual ion-beam assisted deposition

    International Nuclear Information System (INIS)

    Saha, Madhu Sudan; Gulla, Andrea F.; Allen, Robert J.; Mukerjee, Sanjeev

    2006-01-01

    Ultra-low pure Pt-based electrodes (0.04-0.12 mg Pt /cm 2 ) were prepared by dual ion-beam assisted deposition (dual IBAD) method on the surface of a non-catalyzed gas diffusion layer (GDL) substrate. Film thicknesses ranged between 250 and 750 A, these are compared with a control, a conventional Pt/C (1.0 mg Pt(MEA) /cm 2 , E-TEK). The IBAD electrode constituted a significantly different morphology, where low density Pt deposits (largely amorphous) were formed with varying depths of penetration into the gas diffusion layer, exhibiting a gradual change towards increasing crystalline character (from 250 to 750 A). Mass specific power density of 0.297 g Pt /kW is reported with 250 A IBAD deposit (0.04 mg Pt /cm 2 for a total MEA loading of 0.08 mg Pt /cm 2 ) at 0.65 V. This is contrasted with the commercial MEA with a loading of 1 mg Pt(MEA) /cm 2 where mass specific power density obtained was 1.18 g Pt /kW (at 0.65 V), a value typical of current state of the art commercial electrodes containing Pt/C. The principal shortcoming in this effort is the area specific power density which was in the range of 0.27-0.43 W/cm 2 (for 250-750 A IBAD) at 0.65 V, hence much below the automotive target value of 0.8-0.9 W/cm 2 (at 0.65 V). An attempt to mitigate these losses is reported with the use of patterning. In this context a series of patterns ranging from 45 to 80% Pt coverage were used in conjunction with a hexagonal hole geometry. Up to 30% lowering of mass transport losses were realized

  3. Tracking costs of alternatively fueled buses in Florida : [summary].

    Science.gov (United States)

    2011-01-01

    In an effort to address rising fuel costs and environmental concerns, many transit agencies across Florida have introduced alternative fuel technologies to their traditional diesel-powered fleets. Fuel types include biodiesel, compressed natural gas,...

  4. Dual Entwining Structures and Dual Entwined Modules

    OpenAIRE

    Abuhlail, Jawad Y.

    2003-01-01

    In this note we introduce and investigate the concepts of dual entwining structures and dual entwined modules. This generalizes the concepts of dual Doi-Koppinen structures and dual Doi-Koppinen modules introduced (in the infinite case over rings) by the author is his dissertation.

  5. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix; Gregson, James; Wetzstein, Gordon; Raskar, Ramesh; Heidrich, Wolfgang

    2014-01-01

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  6. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix

    2014-06-22

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  7. [Dual pathology].

    Science.gov (United States)

    Rougier, A

    2008-05-01

    Dual pathology is defined as the association of two potentially epileptogenic lesions, hippocampal (sclerosis, neuronal loss) and extrahippocampal (temporal or extratemporal). Epileptic activity may be generated by either lesion and the relative importance of every lesion's epileptogenicity conditions the surgical strategy adopted. Most frequently associated with hippocampal sclerosis are cortical dysplasias. The common physiopathology of the two lesions is not clearly established. Extrahippocampal lesions may be undetectable on MRI (microdysgenesis, for example) and ictal discharge patterns may vary among dual pathology patients. The surgical strategy depends on the location of the extrahippocampal lesion and its relative role in seizure generation; however, reported surgical results suggest that simultaneous resection of mesial temporal structures along with the extrahippocampal lesion should be performed.

  8. Calculation of radiation exposure of the environment of interim storage facilities for the dry storage of spent fuel in dual-purpose casks

    Energy Technology Data Exchange (ETDEWEB)

    Wortmann, B.; Stratmann, W. [STEAG Encotec GmbH, Essen (Germany)

    2004-07-01

    Acceptance problems in the public concerning the transport of spent nuclear fuel elements and a new political objective of the Federal Government have forced the German utilities to embark on on-site interim storage projects for the temporary storage of spent nuclear fuel elements. STEAG encotec GmbH, Essen, Germany, was awarded contracts for the conceptual planning including necessary shielding calculations for the majority of the 13 nuclear sites which opted for the dry storage concept. The capacity of the storage facilities ranges from 80 to 100 casks, according to the storage needs of the plants. The average dose rate at the surface of each cask was limited to 0.5 mSv/h, independent of the type of radiation. These new buildings should not significantly increase the exposure of the public to radiation already originating from the existing nuclear power plant. The layout of the storage building therefore has to ensure that additional target values of 10-20 iSv/y are not exceeded. These very low target values as well as the requirement to avoid high mechanical impacts to the casks in case of external events led to a thickness of walls and ceilings of between 1.2 m and 1.3 m. To remove the decay heat from the casks by natural convection sufficient cross sections of the air inlet and outlet ducts are required.

  9. Adiabatic Liquid Piston Compressed Air Energy Storage

    DEFF Research Database (Denmark)

    Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder

    the system. The compression leads to a significant increase in temperature, and the heat generated is dumped into the ambient. This energy loss results in a low efficiency of the system, and when expanding the air, the expansion leads to a temperature drop reducing the mechanical output of the expansion......), but no such units are in operation at present. The CAES system investigated in this project uses a different approach to avoid compression heat loss. The system uses a pre-compressed pressure vessel full of air. A liquid is pumped into the bottom of the vessel when charging and the same liquid is withdrawn through......-CAES system is significantly higher than existing CAES systems due to a low or nearly absent compression heat loss. Furthermore, pumps/turbines, which use a liquid as a medium, are more efficient than air/gas compressors/turbines. In addition, the demand for fuel during expansion does not occur. •The energy...

  10. Microbunching and RF Compression

    International Nuclear Information System (INIS)

    Venturini, M.; Migliorati, M.; Ronsivalle, C.; Ferrario, M.; Vaccarezza, C.

    2010-01-01

    Velocity bunching (or RF compression) represents a promising technique complementary to magnetic compression to achieve the high peak current required in the linac drivers for FELs. Here we report on recent progress aimed at characterizing the RF compression from the point of view of the microbunching instability. We emphasize the development of a linear theory for the gain function of the instability and its validation against macroparticle simulations that represents a useful tool in the evaluation of the compression schemes for FEL sources.

  11. Mining compressing sequential problems

    NARCIS (Netherlands)

    Hoang, T.L.; Mörchen, F.; Fradkin, D.; Calders, T.G.K.

    2012-01-01

    Compression based pattern mining has been successfully applied to many data mining tasks. We propose an approach based on the minimum description length principle to extract sequential patterns that compress a database of sequences well. We show that mining compressing patterns is NP-Hard and

  12. 40 CFR 94.108 - Test fuels.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Test fuels. 94.108 Section 94.108... EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES Test Procedures § 94.108 Test fuels. (a) Distillate diesel test fuel. (1) The diesel fuels for testing Category 1 and Category 2 marine engines designed to...

  13. QCD as a dual superconductor

    International Nuclear Information System (INIS)

    Zachariasen, F.

    1986-01-01

    The author describes the construction of an effective action describing long-range Yang-Mills theory. This action is motivated by a study of the system of Dyson equations and Ward identities, but cannot (yet) be derived from the underlying quantum theory. The effective action turns out to describe a medium very much like a dual relativistic superconductor; that is, with electric and magnetic fields interchanged. There is a dual Meissner effect, which serves to compress color electric fields into flux tubes, containing quantized units of color electric flux. This produces electric confinement. There is a magnetic condensate, resulting from a spontaneous symmetry breaking analogous to that in the relativistic superconductor, as in the Abelian Higgs model. He gives the motivation leading to the effective action, and describes the quantized electric flux tube solutions. Finally, he mentions briefly some other applications

  14. Compression for radiological images

    Science.gov (United States)

    Wilson, Dennis L.

    1992-07-01

    The viewing of radiological images has peculiarities that must be taken into account in the design of a compression technique. The images may be manipulated on a workstation to change the contrast, to change the center of the brightness levels that are viewed, and even to invert the images. Because of the possible consequences of losing information in a medical application, bit preserving compression is used for the images used for diagnosis. However, for archiving the images may be compressed to 10 of their original size. A compression technique based on the Discrete Cosine Transform (DCT) takes the viewing factors into account by compressing the changes in the local brightness levels. The compression technique is a variation of the CCITT JPEG compression that suppresses the blocking of the DCT except in areas of very high contrast.

  15. The mathematical theory of signal processing and compression-designs

    Science.gov (United States)

    Feria, Erlan H.

    2006-05-01

    The mathematical theory of signal processing, named processor coding, will be shown to inherently arise as the computational time dual of Shannon's mathematical theory of communication which is also known as source coding. Source coding is concerned with signal source memory space compression while processor coding deals with signal processor computational time compression. Their combination is named compression-designs and referred as Conde in short. A compelling and pedagogically appealing diagram will be discussed highlighting Conde's remarkable successful application to real-world knowledge-aided (KA) airborne moving target indicator (AMTI) radar.

  16. Fuel rods

    International Nuclear Information System (INIS)

    Hattori, Shinji; Kajiwara, Koichi.

    1980-01-01

    Purpose: To ensure the safety for the fuel rod failures by adapting plenum springs to function when small forces such as during transportation of fuel rods is exerted and not to function the resilient force when a relatively great force is exerted. Constitution: Between an upper end plug and a plenum spring in a fuel rod, is disposed an insertion member to the lower portion of which is mounted a pin. This pin is kept upright and causes the plenum spring to function resiliently to the pellets against the loads due to accelerations and mechanical vibrations exerted during transportation of the fuel rods. While on the other hand, if a compression force of a relatively high level is exerted to the plenum spring during reactor operation, the pin of the insertion member is buckled and the insertion member is inserted to the inside of the plenum spring, whereby the pellets are allowed to expand freely and the failures in the fuel elements can be prevented. (Moriyama, K.)

  17. Radiological Image Compression

    Science.gov (United States)

    Lo, Shih-Chung Ben